Scientific American September 2009 ■ Volume 301 Number 3

SPECIAL ISSUE: UNDERSTANDING ORIGINS 57 INNOVATIONS and Insights That Shape the September 2009 www.ScientificAmerican.com World Today Origins of Paper Money • Coriolis Effect • lsd Scotch tape • hiv • Cooking Life Love • Blueprints internal-combustion engine The Universe Recorded music • Anthrax • Gamma rays Intermittent windshield wipers COMPUTING the web • asteroids mechanical Loom chocolate graphical perspective The Mind photosynthesis • stirrup ball bearings • carbon • light teeth • cancer buckyballs & nanotubes cupcakes • clocks

CONTENTS features ■

Scientific American September 2009 ■ Volume 301 Number 3

special issue 22

INTRODUCTION 21 In the Beginning By the Editors A powerful urge to understand the beginnings of the cosmos or even life itself fuels the scientific enterprise. 30 COSMOLOGY 22 Origin of the Universe By Michael S. Turner Cosmologists are closing in on the ultimate processes that created and shaped the universe.

NEUROSCIENCE 30 Origin of the Mind By Marc Hauser The first step in figuring out how the 38 human mind arose is determining what distinguishes our mental processes from those of other creatures.

BIOLOGY 38 Origin of Life on Earth By Alonso Ricardo and Jack W. Szostak Fresh clues hint at how originS the first living organisms arose from inanimate matter. 46

INFORMATION TECHNOLOGY es g 46 Origin of Computing ma By Martin Campbell-Kelly ; Getty I The information age began with Corbis the realization that machines could ollins

emulate the work of minds. C hris

C .; ORIGINS ROUNDUP hristiansen; 54 The Start of Everything C In the beginning ... what happened? On The Cover

More than 50 brief articles capture the Life, the universe and ... well ... everything are Photo Researchers, Inc dazzling moment of insight or key advance the subjects of this special single-topic issue on at the outset of a variety of things—from origins. We trace their beginnings and key insights obert Gendlerobert Fromtop on cover: Jen flying cars to paper clips to love. into the physical and life sciences and technology. R

3 From the Editor 14 4 Letters 6 50, 100 & 150 Years Ago 7 News Scan MEDICINE & HEALTH 6 ■ Gene therapy: an interview with an unfortunate pioneer. 9 ■ Swine fl u? How about swine Ebola? TECHNOLOGY ■ Public safety bandwidth goes unused. ■ Quantum entanglement and photosynthesis. ENERGY & ENVIRONMENT ■ Conservation efforts pitted against human rights. ■ The airlines are having trouble recycling. RESEARCH & DISCOVERY ■ Animals have the ability to count. ■ Digging up valuable fossils in suburban New Jersey. 2 0 Critical Mass 1 5 Scientific American Perspectives By Lawrence M. Krauss Scientists studying fossils should learn to share. An update on C. P. Snow’s “two cultures.” 1 6 Sustainable Developments 8 2 Recommendations By Jeffrey D. Sachs Babies’ brains. Naming life. Fictional reads. Prioritize the carbon strategy: ambitious climate and energy legislation risks failure without better focus. 8 4 Anti Gravity By Steve Mirsky 1 8 Skeptic The Kindle and all of its contents. By Michael Shermer Paranoia strikes deep: why people believe in conspiracies. GO tO .cOm “Origins” Online Want more information on origins? Go online for added stories, slide shows, details from the Origins Symposium this past spring, and other extras. 18 84 More at www.Scientifi cAmerican.com/sep2009

Scientifi c American (ISSN 0036-8733), published monthly by Scientifi c American, Inc., 75 Varick Street, 9th Floor, New York, N.Y. 10013-1917. Copyright © 2009 by Scientifi c American, Inc. All rights reserved. No part of this issue may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording for public or private use, or by any information storage or retrieval system, without the prior written permission of the publisher. Periodicals postage paid at New York, N.Y., and at additional mailing offi ces. Canada Post International Publications Mail (Canadian Distribution) Sales Agreement No. 40012504. Canadian BN No. 127387652RT; QST No. Q1015332537. Publication Mail Agreement #40012504. Return undeliverable mail to Scientifi c A merican, P.O. Box 819, Stn Main, Markham, ON L3P 8A2. Subscription rates: one year $34.97, Canada $49 USD, International $55 USD. Postmaster: Send address changes to Scientifi c American, Box 3187, Harlan, Iowa 51537. Reprints available: write Reprint Department, Scientifi c American, Inc., 75 Varick Street, 9th Floor, New York, N.Y. 10013-1917; (212) 451-8877; fax: (212) 355-0408. Subscription inquiries: U.S. and Canada (800) 333-1199; other (515) 248-7684. Send e-mail to [email protected] Printed in U.S.A.

Starter Menu

The editors at Scientiﬁ c Ameri- turn to page 21 for the start of “Origins”— can always look forward to we hope you will nd it candy for the cu- creating our annual single- rious mind. topic issues. These special edi- In an issue focused on beginnings, it tions give us the opportunity also seems appropriate to inaugurate a set to more fully explore an area that is of deep of improvements to Scienti c American’s scienti c and public interest and to share pages. We’ve tightened the design of the ta- that comprehensive package with you. ble of contents, to make it easier to nd About a year ago, when the editorial what you are looking for in each issue. We board rst began discussing possibilities have organized the popular News Scan de- for the issue you now hold in your hands, partment by topic; the adjusted layouts are we decided to harness our ambitions in a easier to navigate, and the stories will con- different way. Instead of narrowly focus- tinue to provide the concise analyses of ing on one subject, we would think more news that you have come to expect. expansively. We settled on an all-encom- A new columnist’s pointed commentary passing topic that would provide the intel- will also sharpen the offerings in the front lectual charge we sought but also would of the magazine. Lawrence M. Krauss, an be fun. We decided to probe some of the astrophysicist, social critic and best-selling most profound questions that humans ask author of The Physics of Star Trek and oth- about our existence, such as, Where did er books, brings a scientist’s perspective Among Our everything we see in the universe today and practice of rational analysis to matters Contributors come from? How did life begin? What led of broad scienti c and policy concern. Fit- to the remarkable sophistication of the hu- tingly, his rst installment examines the MARTIN CAMPBELL-KELLY man mind? We knew we would want to unrealized vision of C. P. Snow, who 50 is a professor in the department of computer science at the University of Warwick in provide in-depth feature articles on key years ago wrote his famous “Two Cul- England, where he specializes in the history topics in technology and in the physical tures” essay. Snow noted the distressing of computing. He is editor of The Collected Works of Charles Babbage. and life sciences. To round out the issue, cultural divide between science and the we also wanted to take on a few dozen arts and hoped for a future that would MARC HAUSER other intellectual puzzles—from the ori- bridge the two. We share that hope. is a professor at Harvard gins of the paper clip to the placenta to pa- Last, Anti Gravity moves to a featured University, where he studies the evolutionary and developmental per money—in shorter pieces. position as the back page, where Steve foundations of the human mind. He is We dedicated extra pages to this issue Mirsky’s wry prose adds an entertaining author of Moral Minds and other books. to encompass the span of our questions, punctuation mark to each issue; ip the ALONSO RICARDO but it still was dif cult to winnow our pages to nd his look at Kindle’s foibles. is a research associate at the Howard wish lists to what could be accommodated As always, we welcome your feedback. ■ Hughes Medical Institute at Harvard University. He has a long-standing interest in print. Naturally, more short stories and ) in the origin of life and studies other items of interest are available at MARIETTE DICHRISTINA self-replicating chemical systems. www.Scienti cAmerican.com. For now, acting editor in chief illustration JACK W. SZOSTAK is professor of genetics at Harvard Medical School. His interest in the laboratory construction of biological structures dates back to work he described in the November 1987 Scientiﬁ c American. ); BRYAN CHRISTIE DESIGN ( MICHAEL S. TURNER pioneered the interdisciplinary union

DiChristina of particle physics, astrophysics and cosmology and led the National Academy study that laid out the vision for the new eld earlier this decade. ETHAN HILL (

® Global Famine ■ Big Government ■ Big Pharma Established 1845

Acting EDITOR IN CHIEF: Mariette DiChristina MANAGING EDITOR: Ricki L. Rusting CHIEF NEWS EDITOR: Philip M. Yam “The only way to save SEnIor writeR: Gary Stix EDITORS: Davide Castelvecchi, Graham P. Collins, the human race Mark Fischetti, Steve Mirsky, Michael Moyer, George Musser, Christine Soares, Kate Wong is to reduce CONTRIBUTING EDITORS: Mark Alpert, our numbers.” Steven Ashley, Stuart F. Brown, W. Wayt Gibbs, Marguerite Holloway, Christie Nicholson, —“Mithremakor” via Michelle Press, John Rennie, Michael Shermer, www.ScientificAmerican.com Sarah Simpson

ASSOCIATE EDITORS, ONLINE: David Biello, MAY 2009 Larry Greenemeier news Reporters, ONLINE: Coco Ballantyne, ■■ John Matson Crash of Civilizations grown only faster than population. On a ART DIRECTOR, online: Ryan Reid The obvious driver of the huge issues per capita basis, the United Nation reports, raised by Lester Brown in “Could Food annual grain yields are up 40 percent dur- ART DIRECTOR: Edward Bell Shortages Bring Down Civilization?” is ing the past five decades. Moreover, mil- ASSISTANT ART DIRECTOR: Jen Christiansen overpopulation. Most rational people will lions of hectares of fallow alluvial (unculti- PHOTOGRAPHY EDITOR: Monica Bradley agree that this planet does have a limit vated and fertile) land exist globally that

COPY DIRECTOR: Maria-Christina Keller to the population of humans it can sup- could be exploited for crop production, es- port. Sooner or later we will reach that pecially via the spread of drip irrigation. Editorial Administrator: Avonelle Wing limit, and then the natural world will U.S. crop yields average approximately SENIOR SECRETARY: Maya Harty abruptly step in and make a major correc- 10 tons per hectare as a result largely of

COPY and PRODUCTION: tion through famine, disease and result- mechanization, fertilizers, pesticides, her- Senior COPY editor: Daniel C. Schlenoff ing conflict. bicides, genetically modified seeds, and in COPY editor: Michael Battaglia “Top it off and let it idle” some instances irrigation. The comparable editorial assistant: Ann Chin managing pRODUCTION EDITOR: Richard Hunt via www.ScientificAmerican.com figure in all of Asia and Latin America is senior pRODUCTION EDITOR: Michelle Wright only about three tons per hectare, leaving As usual, the real problem reverts to massive potential for additional increases ASSOCIATE PUBLISHER, PRODUCTION: William Sherman money. Our current socioeconomic system in global agricultural output. ADVERTISING PRODUCTION MANAGER: Carl Cherebin is predicated on the idea of unlimited eco- Emil Wagner PREPRESS AND QUALITY MANAGER: Silvia De Santis nomic growth. That requires unlimited Malvern, Pa. PRODUCTION MANAGER: Christina Hippeli population growth. In the late 1970s and CUSTOM PUBLISH i ng M A N AG ER: Madelyn Keyes-Milch early 1980s we had achieved zero popula- BROWN REPLIES: It is true that grain production has tion growth. That was not good for busi- expanded faster than population, from 249 kilograms Board of Advisers ness, and corporate America began using per person in 1950 to 342 kilograms per person in the media to steer our cultural conscious- 1984. But since then, it has fallen to an estimated 320 Rita R. Colwell Distinguished Professor, University of Maryland ness back to large families, a trend that kilograms per person for this year. College Park and Johns Hopkins Bloomberg School continues today. The only way to save the As to Wagner’s data on yields, U.S. corn yields an of Public Health human race is to reduce our numbers, and average of 10 tons per hectare, but U.S. wheat yields danny hillis Co-chairman, Applied Minds the only way to do that is to restructure our are under three tons per hectare. Vinod Khosla entire socioeconomic system. The bottom line is that the number of hungry and Founder, Khosla Ventures “Mithremakor” malnourished people in the world, which was declin- M. Granger Morgan via www.ScientificAmerican.com ing historically, bottomed out around 2000 at just Professor and Head of Engineering and Public more than 800 million. That figure is now approaching Policy, Carnegie Mellon University Brown begins his rant by insisting that one billion and is projected by the U.S. Department of Lisa Randall Professor of Physics, Harvard University mankind faces imminent food shortages. Agriculture to hit 1.2 billion within the next decade. George M. Whitesides But based on the actual statistics, this is As to the vast potential for expanding production, Professor of Chemistry, Harvard University complete balderdash. Over the past 50 once grain yields have doubled or tripled, as they years grain production worldwide has have already done in much of the developing world,

including China and India, it then becomes much ing the proposed budget deficits with more difficult to expand production. The billion peo- crushing debt. ® ple who are chronically hungry can only wish that the The “false choice” lies in assuming that potential for expanding world food production is as we must (and should) choose between in- Established 1845 vast and as simple as Wagner claims it to be. curring unsustainable debt and massively increasing taxes to European levels. The

alternative way, of course, is to moderate pRESIDENT: Steven Inchcoombe the growth of spending. This policy option Managing Director, International: escapes mention, but it should not. One Kevin Hause VIC E PRESIDE NT, operations a n d consequence of the substantially higher Administration: Frances Newburg tax burden that many European countries have imposed is that their economies have ma n ag i ng DIREc tOR , consumer mark e ti ng : Christian Dorbandt tended to be more sluggish and less dy- assoc iate DIREc tOR , consumer mark e ti ng : namic than the U.S. economy and that Anne Marie O’Keefe they have paid the price in generally higher Senior Marketing Manager/Retention: rates of unemployment and slower techno- Catherine Bussey Senior Marketing Manager/Acquisition: logical innovation. Patricia Elliott Philip Allen Lacovara Sanibel, Fla. VIC E PRESIDE NT A N D PUBLISHER: Bruce Brandfon vice president, marketing and ■■ Pharma Liabilities sales development: Michael Voss In “Legal Side Effects” [Updates], Kate DIREc tOR , g lobal media solutions: Wilcox claimed that a recent U.S. Supreme Jeremy A. Abbate SALES DEVELOPME NT M A N AG ER: Court decision left drug companies “wide David Tirpack open for lawsuits.” The decision upheld SALES REPRESENTATIVES: Jeffrey Crennan, laws that are much needed, especially in Thomas Nolan, Stan Schmidt Children clamor for food in the village of light of the long-standing practice of phar- Dubie, Democratic Republic of the Congo. PROMOTION MANAGER: Diane Schube maceutical companies to sponsor and pay The photograph is from December 2005. for “research” of the drugs they manufac- V ic e preside nt, f i n a nc e , a n d ture in order to market the drugs’ positive BUSINESS DEVELOPMENT: Michael Florek BUSINESS MANAGER: Marie Maher ■■ Deal or No Deal effects while concealing their dangerous

In a phrase that has become fashionable side effects in patients. The court’s deci- DIRECTOR, ANCILLARY PRODUCTS: Diane McGarvey in the past few months, as new government sion upholds important constitutional officials criticize the policies of their pre- rights afforded to all citizens and should decessors, Jeffrey D. Sachs’s column rests be welcomed by a journal that promotes How to Contact Us on a “false choice.” scientific study. subscriptions For new subscriptions, renewals, gifts, payments, and The column accurately predicts that to John Mininno changes of address: U.S. and Canada, 800-333-1199; pay for dramatically enhanced spending Mininno Law Office outside North America, 515-248-7684 or by the U.S. government under the spend- Collingswood, N.J. www.ScientificAmerican.com ing goals laid out by the new administration, it will be necessary to ramp up the THE EDITORS REPLY: Updates is part of the maga- reprints To order reprints of articles: Reprint Department, percentage of GDP that the government zine’s news coverage, not an editorial. Thus, Wilcox Scientific American, 75 Varick Street, 9th Floor, absorbs through taxes. He predicts that was not expressing her personal opinion nor that of New York, NY 10013-1917; 212-451-8877, these taxes will come from increased taxes Scientific American. fax: 212-355-0408; [email protected] on “the rich”—presumably anyone who makes more than the particular speaker— perm issions plus regressive taxes such as a national Letters to the Editor For permission to copy or reuse material: Permissions Scientific American Department, Scientific American, 75 Varick Street, sales tax or VAT. 75 Varick Street, 9th Floor 9th Floor, New York, NY 10013-1917; 212-451-8877; Sachs observes that in recent decades, New York, NY 10013-1917 www.ScientificAmerican.com/permissions or 212-451-8546 or [email protected] for procedures. Please allow three to six weeks for processing.

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have consumed about 33 percent of gross Letters may be edited for length and clarity. domestic product as compared with aver- We regret that we cannot answer each one. advertisi ng ettersson Post a comment on any article instantly at www.ScientificAmerican.com has electronic contact P age European tax burdens of about 45 per- www.ScientificAmerican.com/ information for sales representatives of Scientific American

nders cent of GDP. He concludes that we must sciammag in all regions of the U.S. and in other countries. -A er

P match European tax levels to avoid fund-

Radiation ■ Punched Cards ■ Earthworms Compiled by Daniel C. Schlenoff

SEPTEMBER 1959 HENRY HUDSON’S 300TH— “The ship ‘Half SEPTEMBER 1859 RADIATION— “What should the citizen Moon’ set sail from Amsterdam April 4th, WORMS— “The common earthworm, conclude about ionizing radiation? Ioniz- 1609, with a crew of eighteen Dutch and though apt to be despised and trodden on, ing radiation has always been with us and English sailors. On September 3rd, the is really a useful creature. According to will be for all foreseeable time. Our genet- ‘Half Moon’ let go her anchor inside of Mr. [Charles] Darwin, they give a kind of ic system is probably well adjusted by nat- Sandy Hook (New Jersey). The week was under tillage to the land, performing the ural selection to normal background radi- spent exploring the bay with a small boat, same below ground that the spade does ation. Added radiation will increase the and ‘they found a good entrance between above for the garden, and the plow for ar- frequency of mutations; most of these will two headlands’ (The Narrows) and thus able soil. Fields which have been over- be harmful. Exposure to radiation in large entered on the 12th of September ‘as fine a spread with lime, burnt marl, or cinder, amounts will increase malignant disease; river as can be found.’ When the replica of become, in time, covered by finely-divided small amounts may possibly do the same. Henry Hudson’s ‘Half Moon’ was lifted by soil. This result, usually attributed by In view of these potentially harmful farmers to the ‘working down’ of effects every reasonable effort these materials, is really due to the should be made to reduce the levels action of earthworms. Mr. Darwin of ionizing radiation to which man says, ‘A field manured with marl has is exposed to the lowest levels that been covered, in the course of 80 can reasonably be attained. As to years, with a bed of earth averaging fallout from nuclear-weapons tests, 13 inches in thickness.’ ” the citizen will conclude that it con- tributes in a small way to world- COTTON MARKET— “The ‘crop year’ wide levels of radiation. For this for cotton has just closed, and it has reason alone the tests should be dis- been somewhat eventful. The previ- continued. —George W. Beadle” ous year of the financial panic had passed with a very small consumption, leaving large stocks of goods SEPTEMBER 1909 in the hands of merchants and con- CENSUS— “The counting at the end siderable supplies of raw materials of each decade of every man, wom- with the manufacturers. Returning an, and child in the United States is ease in the money market has been one of the biggest undertakings the accompanied by abundant crops, government is called upon to as- cheap food, low rates for transpor- sume. To facilitate counting, ma- tation, and a large consumption of chines will be used invented by Mr. goods, promising to absorb the James Powers, a mechanical expert whole of the crop. Up to January, of the Census Bureau, for use in the purchases at home and abroad were thirteenth census, which were successfully THREE CENTURIES OF SHIP DESIGN: Henry very large, at improving prices.” tried in the recent Cuban Census and now Hudson’s Half Moon of 1609 shown in scale with a cross section of the RMS Mauretania, in use in the Division of Vital Statistics. EVIL BROADCLOTH— “Professor Hamilton holder of the record for the fastest crossing The mechanical method for counting the says: ‘Gentlemen have adopted as a na- of the Atlantic in 1909. census requires two types of machines. tional costume a thin, tight-fitting black The keynote of the system, however, is a the floating crane at the Brooklyn navy suit of broadcloth. To foreigners, we seem punched card, which contains the data yard from the deck of the ‘Soestdyk,’ on always in mourning: we travel in black, we

collected by the enumerators, who travel which she was brought over from Holland, write in black, we work in black. Even the VOL. CI, NO. 13; SEPTEMBER 25, 1909 from house to house in every nook and and lowered into the water, there was a day-laborer chooses always the same un- corner of the land. The data include the general expression of surprise at her di- varying, monotonous black broadcloth. It nature and extent of our industries, and minutive appearance; for she was no larger is too thin to be warm in the winter, and

the amount of our wealth.” than a small harbor tug.” too black to be cool in the summer.’ ” AMERICAN, SCIENTIFIC

Medicine & Health Tribulations of a Trial Lessons learned by the scientist behind the first gene therapy death BY MELINDA WENNER

Philadelphia—Ten years ago this month the promise of plicity of the concept. You just put the gene in,” Wilson says. using normal genes to cure hereditary defects crashed and The trial he conducted tested the safety of a therapy for orni- burned, as Jesse Gelsinger, an 18-year-old from Tucson, Ariz., thine transcarbamylase (OTC) deficiency, a rare disorder in which succumbed to multiorgan failure during a gene therapy trial at the liver lacks a functional copy of the OTC gene. The defect pre- the University of Pennsylvania. Today the boardroom of the vents the body from eliminating ammonia, a toxic breakdown Translational Research Lab at the university is filled with arti- product of protein metabolism. The Penn scientists had engi- facts reminiscent of the trial. Books such as Building Public Trust neered a weakened adenovirus, or cold virus, to deliver a normal and Biosafety in the Laboratory sit on the shelves, and “IL-6” copy of the OTC gene into the liver. and “TNF-α” are scribbled on the whiteboard—abbreviations Seventeen patients had undergone treatment before Gelsinger, representing some of the very immune factors that fatally spi- who was in the final cohort—the one receiving the highest dose of raled out of control in Gelsinger’s body. the therapy. Many scientists, as well as the FDA, have raised ques- These allusions to the past aren’t surprising considering how tions as to why Gelsinger was being treated, given that several pa- drastically the clinical trial changed gene therapy and, in partic- tients in earlier cohorts suffered severe liver reactions. Wilson says ular, the career of James M. Wilson, the medical geneticist who that they moved forward because it was “the kind of toxicity we headed Penn’s Institute for Human Gene Therapy, where the test would have expected,” based on their work in animals, and they took place. The U.S. Food and Drug Administration banned it thought it would be manageable. According to Mark Batshaw, from conducting human trials, and director of the Children’s Research Insti- Wilson left his post at the now de- tute at the Children’s National Medical funct institute (but he continued do- Center in Washington, D.C., Wilson and ing research at Penn). He disappeared the rest of the scientific community had from the public spotlight until 2005, to learn the hard way “that what you’ve when the agency announced he could learned from animals will not necessar- begin clinical trials with a designated ily predict what’s going to happen in hu- monitor but could not lead trials for mans.” Batshaw was also involved in the five years and asked him to write an 1999 trial. article about the lessons he has The FDA questioned the decision to learned. He published it in Molecular treat Gelsinger for other reasons, too. Genetics and Metabolism this past Just before starting treatment, Gelsing- April. Since then, he has begun giving er—who suffered from a mild form of university lectures about the impor- the disease—had high levels of ammonia tance of exercising caution as a clini- in his blood, indicating that his liver was cal scientist, especially when it comes not functioning well. But because his lev- to stem cells, which today have the ca- els were within acceptable parameters chet once held by gene therapy. when he had enrolled in the trial three Wilson talks about what happened months earlier, the scientists moved for- in 1999 with a quiet deliberateness ward anyway. Wilson, who was respon- suggestive of a painful topic. “With sible for the protocol and its compliance, what I know now, I wouldn’t have admits now that “the protocol was not proceeded with the study,” he says in written in a way in which there was the boardroom, his back facing the enough clarity to know when the ammo- whiteboard. In the 1990s scientists nia had to be what [level], and that was such as himself, he explains, were too a significant shortcoming.”

caught up in the promise of gene ther- severe setback: James M. Wilson ran the institute Did Gelsinger’s high ammonia levels apy to realize that they did not know where a fatal gene therapy experiment occurred play a role in his death? The question enough about it to warrant human in 1999. He now offers advice to stem cell prompts a long pause from Wilson.

newscom testing. “We were drawn into the sim- researchers so that they can avoid similar mistakes. “Well, I don’t think so,” he says softly.

“But things are rarely proven in biology.” No one knows for sure scientists who develop therapies should not be the ones testing just how the procedure, Gelsinger’s liver function and his im- them in humans. “You can’t be the person who acts on behalf mune response are all connected, but Wilson now believes that of the research subject,” he says. Ultimately, Wilson argues, the teen died from a rare phenomenon called antibody-dependent clinical scientists should always ask themselves this question: enhancement. He may have been exposed to a similar adenovi- “If the worst-case scenario played itself out—not the potential rus in the past, which caused his body to create antibodies against or likely, but the worst—would that be acceptable?” If he had it, Wilson explains. Normally antibodies control a virus when asked himself that question in 1999, Wilson says, he would not the body encounters it again. But occasionally they elicit a dan- have proceeded. gerous immune response. Wilson admits, however, that there is It has been a difficult decade for gene therapy, but Wilson be- no way to prove it, because none of Gelsinger’s pretreatment lieves that its fall from favor was inevitable. Gelsinger’s death blood samples remain. “clearly was a precipitating event,” he says, but “stars were lin- Wilson says that even if Gelsinger did die from a rare and un- ing up, and the field was just going to encounter a difficult time.” foreseeable complication, he is not trying to dodge responsibili- Although some gene therapy trials have seen limited success, ty. “The university here, the field and the families who were re- many have produced adverse reactions in volunteers. lying on us to succeed—I just feel as if I’ve disappointed all of Wilson hasn’t given up on the field, though—he is trying to them,” he says. “Quite frankly I don’t know how many different make it safer. Since 1999, with a grant from GlaxoSmithKline, ways I can say it. [I feel] regret, remorse, awful. I’m sorry.” The his lab has identified 120 new adenovirus-associated viruses that university settled a wrongful death lawsuit brought by the Gel can more easily sneak past the immune system and deliver gene singer family for an undisclosed sum. therapies with lower risk, and he has distributed them to 700 in- In his “lessons learned” article, Wilson advises researchers vestigators around the world for further study. He hopes, as do against putting themselves in situations that might create poten- others, that there will be no more Jesse Gelsingers. tial financial conflicts (in 1992 Wilson had founded a biotech- nology company focused on gene therapy). He also argues that Melinda Wenner is based in New York City. Swine Ebola A new reservoir for the infamous Ebola virus BY BRENDAN BORRELL

Don’t worry, it can’t hurt you—yet. not been previously identified in swine. Scientists have identifiedReston ebola- His team also confirmed pig-to-human virus—a member of the deadly Ebola Ebola transmission, identifying six pig group of hemorrhagic fever viruses—in handlers whose blood tested positive for domestic swine from the Philippines. antibodies to the virus. The individuals Ebola is infamous for being highly conta- showed no symptoms, indicating that this gious and causing death rates as high as 90 strain is as harmless to humans now as it percent in some human outbreaks. This was in 1989. Authorities in Manila had particular strain, first identified in mon- announced preliminary findings in Janu- keys in 1989 in a research laboratory in ary, and McIntosh’s details appear in the Reston, Va., is the only one of the family July 10 Science. that is harmless to humans. McIntosh says there are still a lot of The outbreak in swine was discovered unknowns, including how the virus was in July 2008 in the Philippines during an transmitted to the pigs and whether they investigation of so-called blue ear disease show any symptoms independent of blue in pigs, a respiratory condition that causes ear disease. He worries that the virus’s their ears to turn blue from lack of oxy- passage through pigs could enable it to gen. Investigators there sent tissue and mutate into something more dangerous. blood samples to Michael McIntosh of The research also raises the possibility the U.S. Department of Agriculture at that pigs could become infected with That’s not ALL, FOLKS: Besides the flu, the Plum Island Animal Disease Center lethal Ebola strains. “What is the level Getty Images pigs on farms have been detected O harboring a strain of Ebola virus that in Greenport, N.Y. McIntosh was sur- of risk? We really don’t know,” he says. R

is harmless to humans—so far. prised to find that the tissue samples also “The fact that it shows up in domestic A M AR

contained the Reston strain, which had pigs raises that risk.” A NW

8 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. Technology Radio for Responders As multiband radio for public safety proceeds, digital spectrum for it still lags BY LARRY GREENEMEIER

One lesson in the 9/11 attacks eight years ago was the importance of police of- ficers, firefighters and other first responders being able to communicate with one another. Many died because they did not get the call to evacuate from the World Trade Center towers that were about to collapse. To tackle this problem, the U.S. Department of Homeland Security will begin a pilot program this month to test multiband radios designed to let responders communicate across a number of different radio frequencies. Meanwhile a long-touted nationwide public safety broadband network, made possible by the freeing of broadcast spectrum in the country’s switch to digital television this past June, continues to stagnate. The radios of public safety agencies calling all UNITS: In the 9/11 attacks, emergency responders from different branches had currently operate on separate, discrete fre- trouble communicating with one another. New radios may soon solve that problem, al- quencies, making it impossible for a fire- though a dedicated data band created by the U.S. switch to digital TV remains in limbo. fighter, for example, to communicate with a police officer. “There’s no single band several organizations—including Amtrak it will be used for a national wireless public with enough room for all of the public re- along its Northeast Corridor, the Metro safety broadband network to enable local, sponders,” says David Boyd, director of Area Transit Authority in Washington, state and federal emergency responders to command, control and interoperability in D.C., the 2010 U.S. Olympic Security Plan- send text messages and large amounts of the Homeland Security’s Science and ning Committee and 11 others—began us- data, such as digital images and streaming Technology Directorate. As a result, pub- ing the Thales radio as part of Homeland video. “Public safety doesn’t currently have lic safety agencies have been forced to Security’s program. Each agency will eval- this broadband ability,” Boyd remarks. spread their signals throughout the four uate the radio in the field through pilot tests But the move to make use of the D different frequency bands available to lasting at least 30 days, with the govern- block has hit some snags. Because estab- them—namely, at megahertz frequencies ment publishing the results early next year, lishing a nationwide network on it would of 150, 400, 700 and 800. Boyd says. This test is actually the last of a be costly, the government wants a public- Several manufacturers are developing three-phase program to determine the ra- private partnership to develop the block. multiband radios, but currently only a ver- dio’s viability; it already passed a lab test The proposed wireless broadband net- sion made by Thales Communications in and a nonemergency demonstration on work would be built and used by both Clarksburg, Md., meets criteria set by May 2 at the Kentucky Derby. public-sector emergency responders and Homeland Security—that is, the device is Although the radio voice-communica- private-sector businesses, which would roughly the same size and weight as the ra- tion part of the public safety efforts is pro- also be able to license part of the network dios that police and other responders car- ceeding, first responders will not have an for commercial purposes. ry today, and it costs no more than $5,000, emergency broadband data network any- Although the FCC succeeded in selling similar to the high-end single-band radios time soon. The 700-megahertz band (actu- the right to use the old television spectrum now on the market, Boyd says. (They must ally covering 698 to 806 megahertz), freed in an auction last year (it raked in $20 bil-

Getty Images also work with an auxiliary power pack up from the switch to digital TV, has space lion, twice as much as it expected), it ulti- M that can be charged by a battery.) designated by the Federal Communications mately refused to sell a D block license be- AGAON

R This summer the security personnel of Commission for data. Called the D block, cause it had not been offered enough money

by any of D block’s suitors, Boyd says. Harlin McEwen, chair of the they can auction the block without restriction, which they are un- Public Safety Spectrum Trust (PSST) Corporation—formed in 2007 likely to do.” by the FCC to work with industry to develop the national wireless Although broadband data access is important during emergen- public safety broadband network—gave a more pointed reason: cies, some experts do not think that the delays in its implementa- the companies bidding for the space wanted priority access to the tion will seriously undermine public safety. Voice communication D block space over first responders, even in times of emergency. will continue to be the most important lifeline among responders, Without a proper suitor and with a new FCC chair, Julius Gen- Boyd states, which is why the Homeland Security’s upcoming achowski, confirmed only in late June, McEwen says theFCC has multiband pilot program is so important. “Data are not going to delayed bidding for the D block indefinitely. He plans to meet with replace voice as the fundamental emergency communication, be- Genachowski to discuss the agency officials’ options for the D cause voice is interactive in a way that text will never be,” he notes block. “They can schedule another D block auction with the rule as an example. “In environments where you have to use your eyes that the winner has to work with the PSST,” McEwen says. “Or and hands for other things, you have to be able to talk.” Chlorophyll Power Quantum details of photosynthesis could yield better solar cells BY MICHAEL MOYER

As nature’s own solar cells, plants many different states at once. What’s convert sunlight into energy via photosyn- more, these states can interfere with one thesis. New details are emerging about how another—adding constructively at some the process is able to exploit the strange be- points, subtracting at others. If the energy havior of quantum systems, which could going into the antennas could be broken lead to entirely novel approaches to captur- into an elaborate superposition and made ing usable light from the sun. to interfere constructively with itself, it All photosynthetic organisms use pro- could be transported to the reaction cen- estingly, the fuzzy quantum states in these tein-based “antennas” in their cells to cap- ter with nearly 100 percent efficiency. systems are relatively long-lived, even ture incoming light, convert it to energy A new study by Mohan Sarovar, a though they exist at room temperature and and direct that energy to reaction centers— chemist at the University of California, in complicated biological systems. In quan- critical trigger molecules that release elec- Berkeley, shows that some antennas— tum experiments in the physics lab, the trons and get the chemical conversion roll- namely, those found on a certain type of slightest intrusion will destroy a quantum ing. These antennas must strike a difficult green photosynthetic bacteria—do just superposition (or state). balance: they must be broad enough to ab- that. Moreover, nearby antennas split in- These studies mark the first evidence sorb as much sunlight as possible yet not coming energy between them, which leads of biological organisms that exploit grow so large that they impair their own not just to mixed states but to states that strange quantum behaviors. A better un- ability to shuttle the energy on to the reac- are entangled over a broad (in quantum derstanding of this intersection of micro- Getty Images

tion centers. terms) distance. Gregory Scholes, a chem- biology and quantum information, re- r ne

This is where quantum mechanics be- ist at the University of Toronto, shows in a searchers say, could lead to “bioquantum” g comes useful. Quantum systems can ex- soon to be published study that a species of solar cells that are more efficient than to- tinRue ist in a superposition, or mixture, of marine algae utilizes a similar trick. Inter- day’s photovoltaics. Mar

Energy & Environment Conflicted Conservation Saving the earth might mean trampling indigenous rights BY MADHUSREE MUKERJEE

Even as industrial civilization reaches into the farthest icism that they could drive indigenous people off their lands and corners of the globe to extract resources such as oil, timber and destroy their livelihoods. fish, environmentalists are striving to mitigate its deleterious ef- Conservationists have historically been at odds with the peo- fects on the biosphere. Projects to reduce pollution, prevent cli- ple who inhabit wildernesses. During the last half of the 20th mate change and protect biodiversity, however, are drawing crit- century, millions of indigenous people in Africa, South America

10 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. and Asia were ousted from their homelands to establish nature sanctuaries free of humans. Most succumbed to malnutrition, disease and exploitation, recounts anthropologist Michael Cernea of George Washington University. Such outcomes —coupled with the realization that indigenous groups usually help to stabilize ecosystems by, for instance, keeping fire or invasive weeds at bay—have convinced major conservation groups to take local human concerns into account. The World Wildlife Fund (WWF) now describes indigenous peoples as “natural allies,” and the Nature Conservancy pledges to seek their “free, informed and prior” consent to projects impacting their territories. Recent incidents, however, have made some observers wonder. “They’re talking the talk, but are they walking the walk?” asks Jim Wickens of the advocacy group Forest Peoples Program, based in Moreton-in-Marsh, England. Wickens cites a “huge cry of concern” by 71 grassroots groups protesting a WWF effort to set up a certification scheme for shrimp aquaculture. Shrimp farms have often been established along tropical coastlines by THREATENED TRIBESMAN: The Melayu of Indonesia may lose fishing cutting down mangroves, and their effluents have damaged and hunting grounds to a forest-saving carbon plan. neighboring fisheries and farmlands. The Mangrove Action Proj- ect, an advocacy group based in Port Angeles, Wash., considers title over it. The Nature Conservancy, which supports indigenous intensive shrimp aquaculture impossible to make sustainable. peoples’ efforts to acquire legal rights to their territories, coun- The WWF counters that less than one third of shrimp manu- ters that “increasing the value of forests through REDD can only facturers worldwide are currently achieving the standards that it provide them benefits.” hopes to set. As such, certification should “certainly make shrimp Concerns of displacement are particularly acute in Indonesia, farming cleaner,” says Jason Clay, W W F’s vice president of mar- where villagers opposing logging operations and paper, pulp and kets. Geographer Peter Vandergeest of York University in Toron- palm oil plantations on their territories have experienced violent to worries, however, that the endeavor will falter unless the com- attacks. Some 20 carbon forestry projects are already in the munities that are affected by shrimp farms have a say in setting works there. Colchester warns that the government’s regulations standards and enforcement. Given the remoteness of many on REDD do not adequately protect indigenous peoples. In the shrimp farms, he explains, auditors’ checks will be rare, and Kampar Peninsula, for instance, a forestry company proposes to “you can easily put on a show.” clear-cut a ring of swamp forest and plant it with acacia—so as Perhaps more worrisome to advocates for indigenous peoples, to protect the forest in the core area and thereby earn REDD however, are so-called carbon-offset schemes that seek to protect credits. The project would limit the access of the Melayu people standing forests. Several of the large environmental organi to their traditional fishing creeks and hunting grounds; they have zations hold that the carbon saved by preventing deforestation protested by preventing company staff from entering the area. could be sold as offsets, thereby generating funds for conserva- Similar fears of dispossession color attempts to protect coral tion and communities. A scheme referred to as REDD (reducing reefs. In May six nations in Southeast Asia, with technical sup- emissions from deforestation and degradation) may be intro- port from the Nature Conservancy, WWF and Conservation In- duced this December into the United Nations Climate Change ternational, committed to the Coral Triangle Initiative, which Convention, and it could be partly financed by offsets. The Na- will protect 75,000 square kilometers of coastline, coral reefs ture Conservancy hopes that three billion tons of such credits, and ocean. M. Riza Damanik of KIARA, the Fisheries Justice valued at $45 billion, can be generated by 2020. Coalition of Indonesia, worries that the richest fishing grounds But Marcus Colchester of Forest Peoples Program comments: will be zoned off as protected areas. m “We see a risk that the prospect of getting a lot of money for bio- Environmental psychologist Lea Scherl of James Cook Uni- gra o r diversity could lead to indigenous peoples’ concerns falling by versity in Australia, who has studied the region’s marine protect-

les P the wayside.” In particular, increasing the financial value of for- ed areas, believes that such concerns are justified. In the largest p ests could lead to “the biggest land grab of all time,” claims Tom conservation organizations, she explains, scientists design proj- est Peo r B. K. Goldtooth of the Indigenous Environmental Network, ects on the macro level—as if the map contained only natural fea- o based in Bemidji, Minn. Interpol has warned that unscrupulous tures—and factor in culture afterward. “The people rarely have

tesy of F entities plan to profit from REDD: their methods could include a meaningful voice at the very outset,” she says. Furthermore, ef- r ou

C expelling an indigenous people from their forest to acquire legal forts to mitigate a project’s impacts on local communities are un-

derfunded and often unsystematic, compared with the scientific conservation. As Scherl puts it: “You lose that knowledge when aspects. you take the people away.” In the end, it is those who have intimate details of the land and the seas, accumulated over generations, who hold key insights to Madhusree Mukerjee is a science writer based near Frankfurt. The Not So Green Skies New calls for the U.S. airline industry to take recycling seriously BY DAVID FARLEY

Even the infrequent flier might “There are, for example, waste chutes that observed that had aggressive recycling pro- have noticed that when the flight atten- are all too convenient to dump trash. But grams saved at least $100,000 a year. (Se- dant comes around collecting passenger there’s no chute for recycling.” attle-Tacoma led the way with $180,000.) detritus, all the empty cans, cups, bottles, Some airports, however, have made An approach called commingled recy- newspapers and napkins usually end up in great strides—recycling bins have popped cling may be the easiest way to reduce costs the same garbage bag. The U.S. airline in- up in terminals in recent years. And some and get more airlines to recycle. In this dustry discards enough aluminum cans ev- facilities have taken recycling more seri- method, trash and reusable materials do ery year to build nearly 58 Boeing 747s and ously than others—Fort Lauderdale/Hol- not have to be separated onboard—a ma- enough paper to fill a football field–size lywood International, Seattle-Tacoma In- chine separates the trash from the reusable hole 230 feet deep—that’s 4,250 tons of ternational and Portland International are material and then separates the different aluminum and 72,250 tons of paper. The a few examples. None, however, yet comes types of recyclables. More waste manage- 30 largest airports in the country, with the close to the national recycling rate of 31 ment firms are offering the service to air- help of the airlines, create enough waste to percent of waste. lines. As a result, Delta Airlines, which re- equal the trash produced by cities the cycled onboard trash in only five cit- size of Miami or Minneapolis. ies in 2007, recycled it in 23 cities in Unlike other aspects of the travel 2008. Southwest Airlines and JetBlue business, the airline industry has are in the process of expanding their moved at a snail’s pace to get on- commingled recycling efforts, too. board the green revolution. Although Southwest would not say how much hotels, for instance, have plenty of money it makes from recycling, but a monetary reasons to encourage pa- representative for the airline says the trons not to have their towels changed goal is to pay for its waste manage- every day, the airline industry has lit- ment through recycling rebates and tle economic incentive and even less reduction. government pressure to go green. Despite such recent efforts, Hersh- Several factors have discouraged kowitz doesn’t think the recent efforts airlines and airports from following go far enough, and he hopes that the the nation’s recycling trends, says Al- Obama administration will install TOSSED AWAY: The airline industry in the U.S. len Hershkowitz, a senior scientist at the trashes enough aluminum cans every year some regulations forcing airlines and air- Natural Resources Defense Council to build nearly five dozen jumbo jets. ports to take recycling more seriously. “The (NRDC). In December 2006 he published voluntary system hasn’t worked,” he insists. a report quantifying the waste from the in- The lack of a recycling infrastructure at In January, Hershkowitz met with the Gov- dustry and lambasting it for its lack of ini- airports has meant that an airline that ernment Accountability Office over the tiative toward recycling. wants to recycle must take on the expense problem and recommended that a law be One of the problems is that airports itself—a difficult choice given the financial created requiring that all airports receiving have been reluctant to change their infra- straits in which most airlines find them- federal funds must begin separating recy- structure to accommodate recyclable ma- selves today. But part of the problem, as clables from trash. If the GAO follows terials. Some airlines even separate the re- Hershkowitz claims, is that some do not through, it will issue a report this fall rec- cyclables from the trash onboard the air- realize the payback. “It costs more money ommending the regulation of airport plane, but if the airport is not equipped for to dump in a landfill than it does to put re- recycling. recycling, it all goes into the same place. cyclables on the commodities market and Getty Images ood

“Airports have been designed without re- get some money back,” he says. Hershkow- David Farley, based in New York City, W

cycling in mind,” Hershkowitz explains. itz’s study found that the four airports he writes frequently about travel issues. John

Scientists have been skeptical of worms. “They probably have some innate ied, the monkeys showed no change in ac- claims of mathematical abilities in ani- ability to discern between small numbers” curacy or reaction time. One animal, re- mals ever since the case of Clever Hans as three and four, Burns thinks, but they warded with Kool-Aid, was 10 to 20 per- about 100 years ago. The horse, which also “use their number sense on a daily ba- cent less accurate than college students performed arithmetic and other intellec- sis, and so through trial and error, they but beat them in reaction time. “The mon- tual tasks to delighted European audienc- can train themselves to identify numbers key didn’t mind missing every once in a es, was in reality simply taking subcon- up to 12.” while,” Cantlon recounts. “It wants to get scious cues from his trainer. Modern ex- More recently, in the April issue of the past the mistake and on to the next prob- amples, such as Alex the African grey same Royal Society journal, Rosa Rugani lem where it can get more Kool-Aid, parrot, which could count up to six and of the University of Trento in Italy and her whereas college students can’t shake their knew sums and differences, are seen by team demonstrated arithmetic in newly worry over guessing wrong.” some as special cases or the product of hatched chickens. The scientists reared the Elizabeth Brannon of Duke University conditioning. chicks with five identical objects, and the has conducted similar experiments with Recent studies, however, have uncov- newborns imprinted on these objects, con- rhesus monkeys, getting them to match ered new instances of a counting skill in sidering them their parents. But when the the number of sounds they hear to the different species, suggesting that mathe- scientists subtracted two or three of the number of shapes they see, proving they matical abilities could be more fundamen- original objects and left the remainders can do math across different senses. She tal in biology than previously thought. Un- behind screens, the chicks went looking also tested the monkeys’ ability to do sub- der certain conditions, monkeys could for the larger number of objects, sensing traction by covering a number of objects sometimes outperform college students. that Mom was more like a three and not a and then removing some of them. In all In a study published last summer in the two. Rugani also varied the size of the ob- cases, the monkeys picked the correct re- Proceedings of the Royal Society B, Kevin jects to rule out the possibility the chicks mainder at a rate greater than chance. C. Burns of Victoria University of Wel- were identifying groups based simply on And although they might not grasp the lington in New Zealand and his colleagues the fact that larger numbers of items take deeper concept of zero as a number, the burrowed holes in fallen logs and stored up more space than smaller numbers. monkeys knew it was less than two or one, varying numbers of mealworms (beetle For the past five years Jessica Cantlon conclude Brannon and her colleagues in larvae) in these holes in full view of wild of the University of Rochester has been the May Journal of Experimental Psy- New Zealand robins at the Karori Wild- conducting a series of experiments with chology: General. life Sanctuary. Not only did the robins rhesus monkeys that shows how their nu- Although Brannon feels that animals flock first to the holes with the most meal- merical skills can rival those of humans. do not have a linguistic sense of numbers— worms, but if Burns tricked them, remov- The monkeys, she found, could choose the they aren’t counting “one, two, three” in ing some of the insects when they weren’t lesser of two sets of objects when they their heads—they can do a rough sort of looking, the robins spent twice as long were the same in size, shape and color. math by summing sets of objects without scouring the hole for the missing meal- And when size, shape and color were var- actually using numbers, and she believes that ability is innate. Brannon thinks that it might have evolved from the need for territorial animals “to access the different sizes of competing groups and for forag- ing animals to determine whether it is good to stay in one area given the amount of food retrieved versus the amount of time invested.” ni ga Irene Pepperberg of the Massachusetts Ru a Institute of Technology, famous for her 30-year work with Alex the parrot, says where’s mom? In experiments with chicks imprinted on toy objects, hatchlings tesy of Ros that even bees can learn to discriminate r showed rudimentary number skills when searching behind screens for their parents.

cou among small quantities. “So some degree

www.ScientificAmerican.com SCIENTIFIC AMERICAN 13 © 2009 SCIENTIFIC AMERICAN, INC. News Scan of ‘number sense’ seems to be able to be learned even in inverte- suggest to childhood educators that math, usually taught after brates, and such learning is unlikely without some underlying age four or five, could actually be introduced earlier into the neural architecture on which it is based,” she remarks. curriculum. Understanding the biological basis of number sense in animals could have relevance to people. According to Brannon, it may Michael Tennesen is a science writer based near Los Angeles. Surviving in the Suburbs A fossil search for why some critters made it past the dinosaur-killing event BY CHARLES Q. CHOI

Outside Freehold, N.J.—The water is the American Museum of Natural History. upward as they would have been posed in icy cold and the stone is slippery as I wade The fossils here are not of dinosaurs, but life. Their position suggests they were all in up to my calves. Along the banks of this ammonites. These cousins of squid and oc- snuffed out rapidly, “perhaps by a Pom- slow-flowing stream, guarded by prickly topus were the iconic marine animals of the peii-like disaster, like a pulse of mud,” brambles, lies one of the richest caches of age of dinosaurs, flourishing worldwide for Landman says. To see if these deaths were fossils dating back to the extinction that 300 million years or more before the KT linked with the KT extinction, the re- claimed the dinosaurs. The remains of ma- extinction wiped them out. They bore searchers tested for iridium, the rare metal rine creatures buried here, kept secret to shells that often resembled those of nauti- found throughout the world near the KT prevent looting, tell an unusual tale: rather luses, which rapidly evolved into hundreds boundary, thought by most to be evidence than dying off 65 million years ago, these of different shapes, ornamented with un- of a cosmic impact. creatures lived on afterward, albeit briefly. dulations and bumps. Unexpectedly, the researchers discov- The discovery is causing scientists to re- Amateur paleontologist Ralph Johnson, ered that the iridium was laid down before think why some creatures survived the so- a New Jersey park ranger, discovered am- the pinna layer, which means that the am- called KT extinction while others did not. monites in this stream in 2003 when con- monites and other creatures there died af- Unlike this one, significant fossil sites struction workers exposed them while set- ter the event “by 10 to maybe 100 years,” tend to be found in exotic locales such as the ting up bridge foundations. The site is now Landman concludes. Their survival runs searing hot Gobi Desert or the windswept kept quiet from all but scientists —poachers “counter to everything we’ve been taught,” pampas of Patagonia, areas remote from the have already trawled nearby areas, on the he adds. He plans to go to a site in Den- kind of urban development that can ruin prowl for fossil shark teeth. Although this mark to retrieve more potential evidence them. “You don’t expect to find them here shallow, inconspicuous creek has no for- of ammonite survival past KT. in suburban New Jersey some 90 minutes mal name on maps, after enduring many Their existence in the post-KT world away from New York City,” explains Neil thorns on the way there, Landman and his raises a host of questions. “If they made it Landman, curator of fossil invertebrates at team dubbed it Agony Creek. through this event like they did through At the time of the KT extinction, the other mass extinctions, why didn’t they water level at this site was some 30 take off again?” asks invertebrate paleon- meters higher than it is now. tologist Peter Harries of the University of Landman investigates the South Florida. “Why did the ancestors of iron-rich glauconite rocks the modern nautiluses make it through here with his colleagues and not the ammonites? That’s extremely and students from the mu- intriguing to me, and the broader message seum’s graduate school, us- to me is that mass-extinction events are ing iron spikes and sledgeham- much more complex than we think.” mers to knock off slabs that are The trove’s proximity to cities is a bit of picked apart with screwdrivers a double-edged sword. “In Mongolia, you and fingers. They find the fossil bed don’t really have the danger that a good rich with dozens of species of marine in- site today might be paved over by asphalt vertebrates, such as crabs, snails, clams, tomorrow, and you can’t walk into peo-

sea urchins, large flat oysters and ammo- ple’s backyards,” Landman remarks. “But hoi nites, as well as fish teeth and scales. who knows if we could have found this site les Q. C ar

Past digs unearthed ammonite shells up otherwise without urban development.” h to some 35 centimeters wide. These lay

amid pinna, triangular bivalves that all Charles Q. Choi is a frequent tesy of C off the TURNPIKE: Ammonite trove exists in r

Agony Creek, in suburban New Jersey. died here relatively undisturbed: they jut contributor based in New York City. cou

14 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. ILLUSTRATION BY MATT COLLINS PERSPECTIVES [email protected] month engagement 3.2-million- The City. tract hundreds York of ofthousands visitors New over the in course of her four- arrived of skeleton partial fossil year-old Lucy famed the June In Manhattan Project. Manhattan outsiders to prompting endeavorthe term paleoanthropology’s restricted, highly remains specimens the to access origins, man hu- for of species understanding and this touted the importance the announced White of after years fossils rst teen ered by ofTim Berkeley. White the of Fif- University California, ramidus, pithecus out of science paleoanthropology. scoop or disagree with their own. In so doing, they are taking the that tists from assessments fearing could their studying treasures, scien- other block often hunters fossil Indeed, issue. single-topic this in mention to appropriate seems which origins, human of eld museums turned the exhibit away in part for those reasons. imen out of scienti c for circulation too long. some Indeed, major the bones could damage and sustain that the tour takes a key spec- jections that aired when she rst landed in the U.S.: namely, that Yorkher New ob- same the debut included announcing reports with so many members of the science-interested public. But news delighted by to the opportunity share the discipline’s crown jewel of Ethiopia. One might expect scholars of human evolution to be www.ScientificAmerican.com www.ScientificAmerican.com Paleontologists are overly possessive of human fossils. Science fossils. human of possessive overly are Paleontologists BY THE EDITORS THE BY Fossils for All for Fossils White, for his part, has said that he published only an initial initial an only he that published said has for part, his White, Ardi- of case the to point commonly secrecy such of Critics The objections re ect a larger problem of possessiveness in the Before this tour, Lucy had never been on public display outside a 4.4-million-year-old human ancestor discov- ancestor human 4.4-million-year-old a — part of a six-year tour that began in 2007. in began that tour six-year a of part Australopithecus afarensis

olution olution photographs and CT scans high-res- observations, could searchers measurements, contribute a key specimen key a tion of a assessment. And full he has noted that the condition of publica- until access is to limit practice normal that and report cording to Leslie Aiello of the Wenner-Gren Foundation, a ma- Foundation, of Wenner-Gren the Aiello to Leslie cording paleoan- But frame. thropologists time assert that nothing hased really changed. And ac- speci a within researchers other to making specimens and data collected using for NSF plan a moneyinclude to availableapplicants grant requiring limits, setting the discovery team’s ndings nor test new hypotheses. of science is impeded: outside researchers can neither reproduce aspect self-correcting the of period exclusivity. this Otherwise, scribing and them. analyzing But there should be clear on limits de- at crack deserve rst past humanity’s of remnants the earth report. detailed team’s the of lease The future of may education science depend The on future it. with laypeople the hard evidence for humankind’s ancient roots. in evolution, scientists should embrace to the opportunity share deserve where a staggering proportion of the research, population does U.S., not the as believesuch this countries in of And displayed. and transported much nance who an occasional glimpse of taxpayers, them. Irreplaceable objects are surely routinely tage, new genetic sequences. prior to publication, as they do with authors of papers containing pology. And could journals require that authors submit their data — In 2005 the National Science Foundation took toward steps Foundation Science National the 2005 In to un- tears and sweat blood, the who expend scientists The As As for the public display of of these fragments our shared heri- and the public the and jor source of private funding for anthropological research, both public and private funding agencies typically both lack public and agencies privatetypically funding the resources to enforce access policies, if they have will depend in large part on paleoanthropologists paleoanthropologists on part large in depend will all. at them could also create a centralized database to which re- which to database centralized a create also could sils themselves and the that institutions store human fos- who do not follow the access rules. The agency agency The rules. access the follow not do who applicants repeat those exception without reject again, should take a researcher rmer a stance on the fund issue and to whether deciding in factor one just accessible data tomake failure considers currently which NSF, the But thing. right the ing Ultimately, the adoption of open-access practices practices adoption the ofUltimately, open-access — — most of which originate outside the U.S. the outside originate which of most a badly crushed skeleton crushed badly a — suffers as a result a as suffers — a GenBank for paleoanthro- for GenBank a SCIENTIFIC AMERICAN — has slowed the re- the slowed has — 15 do- ■ SUSTAINABLE DEVELOPMENTS Prioritize the Carbon Strategy The Obama administration needs an energy strategy alongside the ambitious climate bill BY JEFFREY D. SACHS

The U.S. House of Representatives passed the Amer- even if environmentalists turn up their noses at coal, China, India ican Clean Energy and Security Act in June and and other countries will keep on using it heavily. So, too, will the sent it to the Senate. The House bill, running to U.S. The key is to ensure that future coal plants are using CCS. 1,428 pages, aspires in one breathtaking stroke Fourth, we need to develop our tremendous solar potential. to take on renewable energy, carbon capture Investments in large-scale solar power are very likely to pay off and sequestration (CCS), nuclear power, elec- monumentally within years or decades, but an integrated strat- tric vehicles, carbon cap and trade, power transmission, energy egy of R&D, feed-in tariffs and other forms of support to bring ef ciency and climate adaptation. It ranges from grand vision to that great potential to fruition will be essential. minutiae. Fifth, the U.S. must speed and complete the changeover of its Yet missing from this sprawling draft is prioritization. To ac- vehicle eet to a new generation of electric ones, including plug- complish a worldwide, fundamental energy overhaul, we will in hybrids, battery-operated vehicles and fuel-cell automobiles. need to keep our eye on the big picture—the technology systems Either America will learn to produce such cars competitively, or that will make a large, lasting difference—and not get mired in it will end up importing them from China, Europe and Japan. excruciating details. Sixth, we need to exploit the vast, unful lled opportunities Of the dozens of actions discussed in the bill, only half a doz- for fuel ef ciency in electric motors, lightbulbs, appliances, and en or so are likely to make a consequential difference. Putting a home heating and cooling. Energy-ef ciency programs in Califor- price on carbon is the single most important policy, because that nia and Japan during the past 20 years have shown the remarkable will indeed send a signal through the economy to shift to low- gains that can be achieved, often at large savings to consumers. carbon technologies. Alas, a straightforward tax on carbon The bill covers all these topics, along with countless sideshows would be far superior to the cumbersome cap-and-trade system and boondoggles. There is continuing support for a corn-based proposed in the House bill. Politicians hate the word “tax” and biofuel policy, which wastes food supplies and taxpayer dollars like to distribute free emissions permits to powerful interest without doing much to reduce carbon emissions (chalk this policy groups. The result is an overly complicated and somewhat arbi- up to the political weight of the Iowa caucus). trary system but is still much better than nothing. At least car- The White House has so far let Congress bon emissions would nally bear a market price under the legis- do what it does best: to put everything into lation, and the Senate still has time for major improvements. the stew, with every interest group stroked, Ramping up nuclear power is probably the second most impor- compensated or subsidized, but with- tant measure, because it is currently the most scalable, cost-com- out prioritizing the key steps that will petitive source of noncarbon electricity. The legislation is decid- determine success or failure in over- edly ambivalent about nuclear power, re ecting the continuing hauling the energy system. The divisions within the environmental community between advo- administration has shown again cates and staunch foes. Whether or not we choose to expand its deft political touch in nudging nuclear power, China and many other countries cer- the draft legislation through the tainly will. The U.S. should as well; it is House and on to the Senate. Now necessary for a cost-effective reduc- the challenge cries out for a simi- tion of greenhouse gas emissions. larly deft touch in policy design Third, CCS needs to be tested and, and management. ■ if successful, rapidly and extensively deployed. The legislation rightly Jeffrey D. Sachs is director of the Earth Institute at champions CCS, although Columbia University (www.earth.columbia.edu). many environmentalists continue to oppose An extended version of this essay is available at coal unconditionally. www.Scienti cAmerican.com/sep2009

Yet as with nuclear, COLLINS MATT BY ILLUSTRATION INSTITUTE; GILBERT/EARTH BRUCE BY PHOTOGRAPH

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Size: Bleed: 8.375 x 11 Trim: 8.125 x 10.75 SKEPTIC Paranoia Strikes Deep Why people believe in conspiracies BY MICHAEL SHERMER

After a public lecture in 2005, I was buttonholed and agenticity (the bent to believe the world is controlled by invis- by a documentary filmmaker with Michael ible intentional agents). Conspiracy theories connect the dots of Moore-ish ambitions of exposing the conspiracy random events into meaningful patterns and then infuse those pat- behind 9/11. “You mean the conspiracy by Osa- terns with intentional agency. Add to those propensities the con- ma bin Laden and al Qaeda to attack the United rmation bias (which seeks and nds con rmatory evidence for States?” I asked rhetorically, knowing what was what we already believe) and the hindsight bias (which tailors af- to come. ter-the-fact explanations to what we already know happened), and “That’s what they want you to believe,” he said. “Who is they?” we have the foundation for conspiratorial cognition. I queried. “The government,” he whispered, as if “they” might be Examples of these processes can be found in journalist Arthur listening at that very moment. “But didn’t Osama and some mem- Goldwag’s marvelous new book, Cults, Conspiracies, and Secret bers of al Qaeda not only say they did it,” I reminded him, “they Societies (Vintage, 2009), which covers everything from the Free- gloated about what a glorious triumph it was?” masons, the Illuminati and the Bilderberg Group to black helicop- “Oh, you’re talking about that video of Osama,” he rejoined ters and the New World Order. “When something momentous knowingly. “That was faked by the CIA and happens, everything leading up to and leaked to the American press to mislead us. away from the event seems momentous, There has been a disinformation campaign too. Even the most trivial detail seems to going on ever since 9/11.” glow with significance,” Goldwag ex- Conspiracies do happen, of course. plains, noting the JFK assassination as a Abraham Lincoln was the victim of an as- prime example. “Knowing what we know sassination conspiracy, as was Austrian now ... lm footage of Dealey Plaza from archduke Franz Ferdinand, gunned down November 22 , 1963, seems pregnant with by the Serbian secret society called Black enigmas and ironies—from the oddly ex- Hand. The attack on Pearl Harbor was a pectant expressions on the faces of the on- Japanese conspiracy (although some con- lookers on the grassy knoll in the instants spiracists think Franklin Roosevelt was in before the shots were red (What were on it). Watergate was a conspiracy (that they thinking?) to the play of shadows in Richard Nixon was in on). How can we tell the background (Could that ash up there the difference between information and on the overpass have been a gun barrel disinformation? As Kurt Cobain, the rock- gleaming in the sun?). Each odd excres- er star of Nirvana, once growled in his grunge lyrics shortly be- cence, every random lump in the visual texture seems suspicious.” fore his death from a self-in icted (or was it?) gunshot to the head, Add to these factors how compellingly a good narrative story can “Just because you’re paranoid don’t mean they’re not after you.” tie it all together—think of Oliver Stone’s JFK or Dan Brown’s An- But as former Nixon aide G. Gordon Liddy once told me (and gels and Demons, both equally ctional. he should know!), the problem with government conspiracies is What should we believe? Transcendentalists tend to believe that that bureaucrats are incompetent and people can’t keep their everything is interconnected and that all events happen for a rea- mouths shut. Complex conspiracies are dif cult to pull off, and so son. Empiricists tend to think that randomness and coincidence many people want their quarter hour of fame that even the Men in interact with the causal net of our world and that belief should de- Black couldn’t squelch the squealers from spilling the beans. So pend on evidence for each individual claim. The problem for skep- there’s a good chance that the more elaborate a conspiracy theory ticism is that transcendentalism is intuitive; empiricism is not. Or is, and the more people that would need to be involved, the less as folk rock group Buffalo Spring eld once intoned: Paranoia likely it is true. strikes deep. Into your life it will creep ... ■ Why do people believe in highly improbable conspiracies? In previous columns I have provided partial answers, citing patter- Michael Shermer is publisher of Skeptic (www.skeptic.com)

nicity (the tendency to nd meaningful patterns in random noise) and author of Why People Believe Weird Things. PHOTOGRAPH BY BRAD SWONETZ; ILLUSTRATION BY MATT COLLINS

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SciAm7Ad3_20090617_OL.indd 1 6/18/09 8:39 AM Critical mass C. P. Snow in New York A new column that examines the intersection between science and society provides an update on the “two cultures” By Lawrence m. Krauss

Earlier this summer marked the 50th anniversary of accord a special place to religion, in part thanks to groups such C. P. Snow’s famous “Two Cultures” essay, in as the Templeton Foundation, which has spent millions annually which he lamented the great cultural divide that raising the profile of “big questions,” which tend to suggest that separates two great areas of human intellectual science and religious belief are somehow related and should be activity, “science” and “the arts.” Snow argued treated as equals. that practitioners in both areas should build The problem is, they are not. Ultimately, science is at best only bridges, to further the progress of human knowledge and to ben- consistent with a God that does not directly intervene in the dai- efit society. ly operations of the cosmos, certainly not the personal and an- Alas, Snow’s vision has gone unrealized. Instead literary agent cient gods associated with the world’s great religions. Even John Brockman has posited a “third culture,” of scientists who though, as physicist Steven Weinberg has emphasized, most peo- communicate directly with the public about their work in media ple who call themselves religious tend to adhere to only those bits such as books without the intervening assistance of literary types. and pieces from scripture that appeal to them, by according un- At the same time, many of those in the humanities, arts and due respect for ancient religious beliefs in general, we nonethe- politics remain content living within the walls of scien- less are suggesting that they are on par with conclusions tific illiteracy. that have been drawn from centuries of rational empiri- Good reasons exist for this phenomenon. In the cal investigation. first place, while we bemoan the lack of good science Snow hoped for a world that is quite different from teaching in our public schools (the vast majority of how we live today, where indifference to science has, middle school physical science and math teachers, for through religious fundamentalism, sometimes morphed example, do not have a science degree), scientific illiter- into open hostility about concepts such as evolution and acy is not a major impediment to success in business, the big bang. politics and the arts. At the university level, science is Snow did not rail against religion, but ignorance. As too often seen as something needed merely to fulfill a the moderator in my panel finally understood after requirement and then to be dispensed an hour of discussion, the only with. To be fair, the same is often the vague notions of God that case for humanities courses for sci- may be compatible with science and engineering majors, ence ensure that God is es- but the big difference is that sentially irrelevant to both these students cannot help our understanding of nature but be bombarded by litera- and our actions based on it. ture, music and art else- Until we are willing to ac- where as a part of the pop cept the world the way it is, culture that permeates without miracles that all daily life. And what’s empirical evidence ar- more, individuals often gues against, without proudly proclaim that science isn’t their thing, almost as a badge myths that distort our comprehension of nature, we are unlikely of honor to indicate their cultural bent. to bridge the divide between science and culture and, more im- There is another factor, one that was on display at the World portant, we are unlikely to be fully ready to address the urgent Science Festival in New York City this summer, which helps to technical challenges facing humanity. ■ undermine the role of science in society. Amid events on the cos- oswell; illustration by matt collins mos, modern biology, quantum mechanics and other areas at the Lawrence M. Krauss, a theoretical physicist, commentator h by john B forefront of science, I participated in a panel discussion on sci- and book author, is Foundation Professor and director of p ence, faith and religion. the Origins Initiative at Arizona State University

Why would such an event be a part of a science festival? We (http://krauss.faculty.asu.edu). Photogra

20 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. BRYAN CHRISTIE DESIGN IN THE BEGINNING THE IN A and owers, whatnot rocks, world populated by iPhones and reruns of reruns and by iPhones world populated world. An urge to deduce beginnings energizes the entire scienti c c scienti entire the energizes beginnings deduce to urge An world. vision foras ofthe latest substitute Thales’ abe candidates wet such questions as whether in particles nitesimal, stringlike may State Arizona University to launch an to Initiative Origins ponder eludes philosophers. today’s natural basic ingredient of matter of ingredient basic losophy and science. A de nitive of phi- answer histories in citation as a only passing to persists cosmology the identity of the most aqueous Thales’ although millennia, ensuing in ceased not has moisture. of element if rock, sand and other substances appeared to be devoid basic single the be how could water asked student), graduate a called be would what (today Thales of disciple a Anaximander, provokedence), observation immediately Thales’ an argument. stituent of matter from which the earth’s denizens earth’s the which from matter of stituent con- it that fundamental was the or posited and gas solid liquid, ofThales inanimate. noticedMiletus that water could exist as a www.ScientificAmerican.com www.ScientificAmerican.com the cosmos or even life itself fuels the scientiﬁc enterprise In In early April a colloquy of 70 leading scientists assembled at The bickering about beginnings and the nature of our existence sci- as now (a known philosophy pursuit natural all with As Greek statesman Greek who statesman lived in the century sixth forward the rst explanation, shorn of theological trap- theological of shorn pings, that captured explanation, the essence of rst all things living and the forward A powerful urge to understand the emergence of — and how it could ultimately lead to a — somehow sprang forth. somehow sprang forth.

American Idol American © 2009 SCIENTIFIC AMERICAN, INC. AMERICAN, © SCIENTIFIC 2009 — men, men, goats, B.C. B.C. — still still put of fascination about of the world fascination us. around endeavor ginnings inventions. human remarkable of series a to dition contemplates in ad- phenomena, of of and dozens biological inception physical technology of A mind. of the human the chronicles brief provides section nal historian a Then the rst computer, perhaps invention the most extraordinary ofanimal’s. other any of gist takes on what has made the human mind different from that ways possible life in which ist addresses and a biolo- rst started, with the overarching question of how the universe began. A chem- ology and technology. In the a pages, following physicist grapples Scienti c American showed chemists of team ously spontane- from form a warm could soup British life A of of organic blocks chemicals. building matter. basic the of one that inanimate from sprang ni cant advance toward the milestone of demonstrating how life Charles Darwin’s of of the publication Appropriately, year’s this 150th anniversary Whether related to rainbows, antibiotics or money,paper be- antibiotics to related rainbows, Whether of issue single-topic this why is themes these of immediacy The www.Scienti cAmerican.com/sep2009 at topic this about information additional Find Read More ... — — and and the stories they generate and of course that extends into the ofrealm biology. On the Origin of Species of Species the Origin On is is devoted to in origins physics, bi- chemistry, SCIENTIFIC AMERICAN — serve as an endless source coincides with a sig- with coincides — s r o t i d E e h T 21 THE UNIVERSE BY michael s. Turner

Cosmologists are closing in on the ultimate processes that created and shaped the universe

he universe is big in both space and time and, for much of humankind’s history, was beyond the reach of our instruments Tand our minds. That changed dramatically in the 20th century. The advances were driven equally by powerful ideas —from Ein- stein’s general relativity to modern theories of the elementary particles—and powerful instruments—from the 100- and 200-inch reflec- tors that George Ellery Hale built, which took us beyond our Milky Way galaxy, to the Hubble Space Telescope, which has taken us back to the birth of galaxies. Over the past 20 years the pace of progress has accelerated with the realization that dark matter is not made of ordinary atoms, the discovery of dark energy, and the dawning of Key Concepts bold ideas such as cosmic inflation and the multiverse. ■ ■ Our universe began with a hot The universe of 100 years ago was simple: eternal, unchanging, big bang 13.7 billion years ago consisting of a single galaxy, containing a few million visible stars. and has expanded and cooled The picture today is more complete and much richer. The cosmos be- ever since. It has evolved from gan 13.7 billion years ago with the big bang. A fraction of a second a formless soup of elementary after the beginning, the universe was a hot, formless soup of the most particles into the richly elementary particles, quarks and leptons. As it expanded and cooled, structured cosmos of today. layer on layer of structure developed: neutrons and protons, atomic ■ ■ The first microsecond was the nuclei, atoms, stars, galaxies, clusters of galaxies, and finally super- formative period when matter clusters. The observable part of the universe is now inhabited by 100 came to dominate over billion galaxies, each containing 100 billion stars and probably a ) antimatter, the seeds for

similar number of planets. Galaxies themselves are held together by styling galaxies and other structures were planted, and dark matter the gravity of the mysterious dark matter. The universe continues to (the unidentified material expand and indeed does so at an accelerating pace, driven by dark that holds those structures energy, an even more mysterious form of energy whose gravitational

together) was created. force repels rather than attracts. ); Gene Burkhardt ( The overarching theme in our universe’s story is the evolution ■ ■ The future of the universe lies in the hands of dark energy, from the simplicity of the quark soup to the complexity we see today

an unknown form of energy that in galaxies, stars, planets and life. These features emerged one by one photoillustration caused cosmic expansion to over billions of years, guided by the basic laws of physics. In our jour- begin accelerating a few billion ney back to the beginning of creation, cosmologists first travel

years ago. —The Editors through the well-established history of the universe back to the first holly lindeM ( origin of origin

22 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. www.ScientificAmerican.com SCIENTIFIC AMERICAN 23 © 2009 SCIENTIFIC AMERICAN, INC. [The Author] microsecond; then to within 10–34 second of the becomes denser, hotter, more extreme and sim- beginning, for which ideas are well formed but pler. In exploring the beginning, we also probe the evidence is not yet firm; and finally to the ear- the inner workings of nature by taking advan- liest moments of creation, for which our ideas tage of an accelerator more powerful than any are still just speculation. Although the ultimate built on Earth—the big bang itself. origin of the universe still lies beyond our grasp, By looking out into space with telescopes, as- we have tantalizing conjectures, including the tronomers peer back in time —and the larger the notion of the multiverse, whereby the universe telescope, the farther back they peer. The light comprises an infinite number of disconnected from distant galaxies reveals an earlier epoch, subuniverses. and the amount this light has redshifted indi- Michael S. Turner pioneered the cates how much the universe has grown in the interdisciplinary union of particle Expanding Universe intervening years. The current record holder has physics, astrophysics and cosmolo- Using the 100-inch Hooker telescope on Mount a redshift of about eight, representing a time gy and led the National Academy Wilson in 1924, Edwin Hubble showed that when the universe was one-ninth its present size study that laid out the vision for fuzzy nebulae, studied and speculated about for and only a few hundred million years old. Tele- the new field earlier this decade. He is a professor at the Kavli several hundred years, were galaxies just like our scopes such as the Hubble Space Telescope and Institute for Cosmological Physics own—thereby enlarging the known universe by the 10-meter Keck telescopes on Mauna Kea at the University of Chicago. 100 billion. A few years later he showed that gal- routinely take us back to the epoch when galax- From 2003 to 2006 he headed axies are moving apart from one another in a ies like ours were forming, a few billion years af- the National Science Foundation regular pattern described by a mathematical ter the big bang. Light from even earlier times is mathematical and physical sciences directorate. His honors include relation now known as Hubble’s law, according so strongly redshifted that astronomers must the Warner Prize of the American to which galaxies that are farther away are mov- look for it in the infrared and radio bands. Up- Astronomical Society, the Lilien- ing faster. It is Hubble’s law, played back in time, coming telescopes such as the James Webb Space feld Prize of the American Physical that points to a big bang 13.7 billion years ago. Telescope, a 6.5-meter infrared telescope, and Society and the Klopsted Award Hubble’s law found ready interpretation with- the Atacama Large Millimeter Array (ALMA), from the American Association of Physics Teachers. in general relativity: space itself is expanding, a network of 64 radio dishes in northern Chile, and galaxies are being carried along for the ride will take us back to the birth of the very first [see box below]. Light, too, is being stretched, or stars and galaxies. redshifted—a process that saps its energy, so that Computer simulations say those stars and gal- the universe cools as it expands. Cosmic expan- axies emerged when the universe was about 100 sion provides the narrative for understanding million years old. Before then, the universe went how today’s universe came to be. As cosmolo- through a time called the “dark ages,” when it gists imagine rewinding the clock, the universe was almost pitch-black. Space was filled with a

[primer] Cosmic Expansion The evolution of the universe is driven by the expansion of space. As space stretches like the rubber in an inflating balloon, galaxies move apart and light waves elongate (hence redden).

); Turner oratory ( b a ) ational L illustration onne N g r as ( m ho elissa T m Courtesy of A

24 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. [CoSMIC TIMeLINe] featureless gruel, fi ve parts dark matter and one part hydrogen and helium, that thinned out as the universe expanded. Matter was slightly un- Before the Big Bang even in density, and gravity acted to amplify Cosmologists do not yet know how the universe began, but these density variations: denser regions expand- this question has now come within the realm of science, with ed more slowly than less dense ones did. By 100 a number of speculative scenarios being discussed. million years the densest regions did not merely expand more slowly but actually started to collapse. Such regions contained about one million No previous era A Matter, energy, space and time solar masses of material each. They were the fi rst begin abruptly with the bang gravitationally bound objects in the cosmos. Dark matter accounted for the bulk of their mass but was, as its name suggests, unable to emit or absorb light. So it remained in an extended cloud. Hydrogen and helium gas, on the other hand, emitted light, lost energy and became con- Quantum emergence centrated in the center of the cloud. Eventually it B ordinary space and time develop collapsed all the way down to stars. These fi rst out of a primeval state described by a quantum theory of gravity stars were much more massive than today’s— –43 hundreds of solar masses. They lived very short 10 second Planck era: earli- lives before exploding and leaving behind the est meaningful fi rst heavy elements. Over the next billion years time; space and or so the force of gravity assembled these mil- time take shape lion-solar-mass clouds into the fi rst galaxies. Radiation from primordial hydrogen clouds, Multiverse greatly redshifted by the expansion, should be C our universe and others bud off detectable by giant arrays of radio antennas from eternal space with a total collecting area of up to one square kilometer. When built, these arrays will watch as the fi rst generation of stars and galaxies ion- ize the hydrogen and bring the dark ages to an end [see “The Dark Ages of the Universe,” by Cyclic universe Abraham Loeb; Scientific American, No- D The big bang is the latest stage vember 2006]. in an eternal cycle of expansion, collapse and renewed expansion ) Faint Glow of a Hot Beginning (from previous cycle) Beyond the dark ages is the glow of the hot big illustration bang at redshift of 1,100. This radiation has been redshifted from visible light (a red-orange glow) satellite discovered that the intensity of the CMB beyond even the infrared to microwaves. What has slight variations—about 0.001 percent—re-

); Melissa thoMas ( we see from that time is a wall of microwave radi- fl ecting a slight lumpiness in the distribution of ation filling the sky—the cosmic microwave matter. The degree of primordial lumpiness was background radiation (CMB) discovered in 1964 enough to act as seeds for the galaxies and larg- by Arno Penzias and Robert Wilson. It provides er structures that would later emerge from the a glimpse of the universe at the tender age of action of gravity. The pattern of these variations Hubble Ultra Deep Field 380,000 years, the period when atoms formed. in the CMB across the sky also encodes basic Before then, the universe was a nearly uniform properties of the universe, such as its overall den- soup of atomic nuclei, electrons and photons. As sity and composition, as well as hints about its , nasa and esa ( it cooled to a temperature of about 3,000 kelvins, earliest moments; the careful study of these vari- the nuclei and electrons came together to form ations has revealed much about the universe [see atoms. Photons ceased to scatter off electrons illustration on page 27]. huBBLe uLTrA DeeP FIeLD, the most and streamed across space unhindered, revealing As we roll a movie of the universe’s evolution

University of Arizona sensitive optical image of the the universe at a simpler time before the existence back from that point, we see the primordial plas- cosmos ever made, reveals more of stars and galaxies. ma becoming ever hotter and denser. Prior to than 1,000 galaxies in their early

r. thoMPsonr. In 1992 NASA’s Cosmic Background Explorer about 100,000 years, the energy density of radi- stages of formation.

www.ScientificAmerican.com Scientific AmericAn 25 © 2009 SCIENTIFIC AMERICAN, INC. © 2009 SCIENTIFIC AMERICAN, INC. The cosmic timeline continues with fairly well-established events leading to the present day. earliest Moments of the Big Bang Formation of Atoms

10–35 second 10–30 s 10–11 s 10–10 s 10–5 s 0.01–300 s 380,000 years Cosmic infl ation one potential Matter gains A second poten- Protons and helium, lithium, Atoms form from creates a large, type of dark the upper hand tial type of neutrons form and heavy hydro- nuclei and electrons, smooth patch of matter (axions) over antimatter dark matter from quarks gen nuclei form releasing the cosmic space fi lled with is synthesized (neutralinos) from protons microwave back- lumpy quark soup is synthesized and neutrons ground radiation

ation exceeded that of matter, which kept mat- correspondence is a great triumph. That these ter from clumping. Thus, this time marks the be- two very different measures, one based on nucle- ginning of gravitational assembly of all the struc- ar physics when the universe was a second old ture seen in the universe today. Still further back, and the other based on atomic physics when the when the universe was less than a second old, universe was 380,000 years old, agree is a strong atomic nuclei had yet to form; only their constit- check not just on our model of how the cosmos uent particles—namely, protons and neutrons— evolved but on all of modern physics. existed. Nuclei emerged when the universe was seconds old and the temperatures and densities Answers in the Quark Soup were just right for nuclear reactions. This pro- Earlier than a microsecond, even protons and cess of big bang nucleosynthesis produced only neutrons could not exist and the universe was a the lightest elements in the periodic table: a lot soup of nature’s basic building blocks: quarks, of helium (about 25 percent of the atoms in the leptons, and the force carriers (photons, the W universe by mass) and smaller amounts of lithi- and Z bosons and gluons). We can be confi dent um and the isotopes deuterium and helium 3. that the quark soup existed because experi- The rest of the plasma (about 75 percent) stayed ments at particle accelerators have re-created in the form of protons that would eventually be- similar conditions here on Earth today [see come hydrogen atoms. All the rest of the ele- “The First Few Microseconds,” by Michael ments in the periodic table formed billions of Riordan and William A. Zajc; Scientific years later in stars and stellar explosions. American, May 2006]. Nucleosynthesis theory accurately predicts To explore this epoch, cosmologists rely not BuLK oF uNIverSe consists of the abundances of elements and isotopes mea- on bigger and better telescopes but on powerful dark energy and dark matter, sured in the most primeval samples of the uni- ideas from particle physics. The development of neither of which has been identifi ed. ordinary matter verse—namely, the oldest stars and high-redshift the Standard Model of particle physics 30 years of the kind that makes up gas clouds. The abundance of deuterium, which ago has led to bold speculations, including string stars, planets and interstellar is very sensitive to the density of atoms in theory, about how the seemingly disparate fun- gas accounts for only the universe, plays a special role: its measured damental particles and forces are unifi ed. As it a small fraction. value implies that ordinary matter amounts to turns out, these new ideas have implications for 4.5 ± 0.1 percent of the total cosmology that are as important as the original energy density. (The re- idea of the hot big bang. They hint at deep and mainder is dark mat- unexpected connections between the world of ter and dark ener- the very big and of the very small. Answers to gy.) This estimate three key questions—the nature of dark matter,

71.5% Dark energy 24% Dark matter ) agrees precisely the asymmetry between matter and antimatter, with the com- and the origin of the lumpy quark soup itself— position that are beginning to emerge. illustrations has been gleaned It now appears that the early quark soup phase from the analysis was the birthplace of dark matter. The identity

of the CMB. This of dark matter remains unclear, but its existence Melissa thoMas (

380,000–300 million yr 300 million yr 1 billion yr 3 billion yr 9 billion yr 10 billion yr 13.7 billion yr gravity continues to First stars and Limit of current Clusters of galax- Solar system Dark energy Today amplify density differences galaxies form observations ies form; star forms takes hold in the gas that fi lls space (highest-redshift formation peaks and expansion objects) begins to accelerate

is very well established. Our galaxy and every nally had equal amounts of each, but at some other galaxy as well as clusters of galaxies are point it developed a slight excess of matter— held together by the gravity of unseen dark mat- about one extra quark for every billion anti- ter. Whatever the dark matter is, it must interact quarks. This imbalance ensured that enough weakly with ordinary matter; otherwise it would quarks would survive annihilation with anti- have shown itself in other ways. Attempts to fi nd quarks as the universe expanded and cooled. a unifying framework for the forces and particles More than 40 years ago accelerator experiments of nature have led to the prediction of stable or revealed that the laws of physics are ever so long-lived particles that might constitute dark slightly biased in favor of matter, and in a still to matter. These particles would be present today be understood series of particle interactions very as remnants of the quark soup phase and are pre- early on, this slight bias led to the creation of the dicted to interact very weakly with atoms. quark excess. One candidate is the called the neutralino, the The quark soup itself is thought to have aris- lightest of a putative new class of particles that en at an extremely early time—perhaps 10 –34 are heavier counterparts of the known particles. second after the big bang in a burst of cosmic ex- The neutralino is thought to have a mass be- pansion known as infl ation. This burst, driven tween 100 and 1,000 times that of the proton, by the energy of a new fi eld (roughly analo- just within the reach of experiments to be con- gous to the electromagnetic fi eld) called the ducted by the Large Hadron Collider at CERN infl aton, would explain such basic prop- near Geneva. Physicists have also built ultrasen- erties of the cosmos as its general unifor- sitive underground detectors, as well as satellite mity and the lumpiness that seeded gal- and balloon-borne varieties, to look for this par- axies and other structures in the uni- ticle or the by-products of its interactions. verse. As the inflaton field decayed A second candidate is the axion, a superlight- away, it released its remaining energy ) weight particle about a trillionth the mass of the into quarks and other particles, thus electron. Its existence is hinted at by subtleties creating the heat of the big bang and the that the Standard Model predicts in the behav- quark soup itself. ior of quarks. Efforts to detect it exploit the fact Infl ation leads to a profound connection that in a very strong magnetic fi eld, an axion can between the quarks and the cosmos: quantum cosmic microwave radiation microwave cosmic transform into a photon. Both neutralinos and fl uctuations in the infl aton fi eld on the subatom- axions have the important property that they ic scale get blown up to astrophysical size by CoSMIC MICroWAve background are, in a specifi c technical sense, “cold.” Al- the rapid expansion and become the seeds for radiation is a snapshot of the universe at the tender age of though they formed under broiling hot condi- all the structure we see today. In other words, 380,000 years. Tiny variations in tions, they were slow-moving and thus easily the pattern seen on the CMB sky is a giant im- the intensity of the radiation clumped into galaxies. age of the subatomic world. Observations of (color-coded here) are a cosmic The early quark soup phase probably also the CMB agree with this prediction, providing rosetta Stone that reveals key holds the secret to why the universe today con- the strongest evidence that infl ation or some- features of the universe, includ- tains mostly matter rather than both matter and thing like it occurred very early in the history ing its age, density, geometry

MaX teGMark and anGeliCa de oliVera-Costa ( antimatter. Physicists think the universe origi- of the universe. and overall composition.

www.ScientificAmerican.com Scientific AmericAn 27 © 2009 SCIENTIFIC AMERICAN, INC. Birth of the Universe led to some remarkable speculations about our As cosmologists try to go even further to under- very beginnings. String theory, for example, pre- stand the beginning of the universe itself, our dicts the existence of additional dimensions of ideas become less fi rm. Einstein’s general theory space and possibly other universes fl oating in of relativity has provided the theoretical foun- that larger space. What we call the big bang may dation for a century of progress in our under- have been the collision of our universe with an- standing of the evolution of the universe. Yet other [see “The Myth of the Beginning of Time,” it is inconsistent with the other pillar of contem- by Gabriele Veneziano; Scientific American, porary physics, quantum theory , and the dis- May 2004]. The marriage of string theory with cipline’s greatest challenge is to reconcile the the concept of infl ation has led perhaps to the two. Only with such a unifi ed theory will we boldest idea yet, that of a multiverse—namely, be able to address the very earliest moments of that the universe comprises an infi nite number the universe, the so-called Planck era prior to of disconnected pieces, each with its own local about 10 –43 second, when spacetime itself was laws of physics [see “The String Theory Land- taking shape. scape,” by Raphael Bousso and Joseph Polchin-

Tentative attempts at a unifi ed theory have ski; Scientific American, September 2004]. thoMas Melissa

The Future Predictable events such as galactic collisions dominate the near future. But the ultimate destiny Acceleration ends 100 trillion years of our universe hinges on A and universe Last stars burn out whether dark energy will expands eternally continue to cause cosmic expansion to accelerate. Broadly, four fates are possible.

30 billion years Acceleration Cosmic redout: cosmic acceleration pulls all other galaxies B continues out of our view; all evidence of the big bang is lost

20 billion years Milky Way collides with Andromeda galaxy

Acceleration 50 billion years intensifi es Big rip: dark energy tears apart all C structures, from superclusters to atoms

Acceleration changes 30 billion years D to rapid deceleration Big crunch, perhaps followed by and collapse a new big bang in an eternal cycle

(to next cycle)

Scientific AmericAn 28 © 2009 SCIENTIFIC AMERICAN, INC. [cosmic acceleration and dark energy] In the Dark central feature of our current view of the universe, as well quantum vacuum energy do not match the amount required by A as its biggest mystery, is dark energy, the recently discov- observations; in fact, they exceed it by many orders of magni- ered and very weird form of energy that is causing cosmic ex- tude. Alternatively, cosmic acceleration might be driven not by pansion to speed up. Dark energy took control from matter a new type of energy but by a process that mimics such energy, a few billion years ago. Prior to that, the expansion had been perhaps the breakdown of general relativity or the influence slowing because of the gravitational attraction exerted by of unseen spatial dimensions [see “A Cosmic Conundrum,” by matter, and gravity was able to forge structures from galaxies Lawrence M. Krauss and Michael S. Turner; Scientific Am e r i c a n , to superclusters. Now, because of the influence of dark energy, September 2004]. structures larger than superclusters cannot form. In fact, had If the universe continues to accelerate at the current rate, then dark energy taken over earlier than it did—say, when the uni- in 30 billion years all traces of the big bang will disappear [see verse was only 100 million years old—structure formation would “The End of Cosmology?” by Lawrence M. Krauss and Robert J. have ceased before even galaxies could have developed, and we Scherrer; Scientific Am e r i c a n , March 2008]. The light from all but would not be here. a handful of nearby galaxies will be too redshifted to detect; the Cosmologists have only rudimentary clues as to what dark temperature of the cosmic background radiation will be too low energy might be. To speed up expansion requires a repulsive to measure; and the universe will appear similar to one that force, and Einstein’s general theory of relativity predicts that the astronomers knew 100 years ago before their instruments were gravity of an extremely elastic form of energy can be actually be powerful enough to reveal the universe we know today. —M.S.T. repulsive. The quantum energy that fills empty space acts in this way. The trouble is that theoretical estimates of the amount of

The multiverse concept, which is still in its in- of the universe by fancy, turns on two key theoretical findings. a mere factor of First, the equations describing inflation strongly 100 billion and suggest that if inflation happened once, it should C o p e r n i c u s ’s happen again and again, with an infinite number banishment of of inflationary regions created over time. Noth- Earth from the ing can travel between these regions, so they have center of the uni- no effect on one another. Second, string theory verse in the 16th centu-

suggests that these regions have different physi- ry seem like small advances If the universe had even more cal parameters, such as the number of spatial di- in the understanding of our place in the cosmos. dark energy than it does, it mensions and the kinds of stable particles. Modern cosmology has humbled us. We are would have remained almost The idea of the multiverse provides novel an- made of protons, neutrons and electrons, which formless (left), without the large swers to two of the biggest questions in all of sci- together account for only 4.5 percent of the uni- structures that we see (right). ence: what happened before the big bang and verse, and we exist only because of subtle con- why the laws of physics are as they are (Einstein’s nections between the very small and the very famous musing about “whether God had any large. Events guided by the microscopic laws of ➥ More To choice” about the laws). The multiverse makes physics allowed matter to dominate over anti- Explore moot the question of before the big bang, because matter, generated the lumpiness that seeded gal- there were an infinite number of big bang begin- axies, filled space with dark matter particles that The Early Universe. Edward W. Kolb nings, each triggered by its own burst of infla- provide the gravitational infrastructure, and en- and Michael S. Turner. Westview Press, 1994. tion. Likewise, Einstein’s question is pushed sured that dark matter could build galaxies be- aside: within the infinity of universes, all possi- fore dark energy became significant and the ex- The InflationaryU niverse. Alan bilities for the laws of physics have been tried, so pansion began to accelerate [see box above]. At Guth. Basic, 1998.

Institute for Computational Cosmology, Durham University Durham Cosmology, Computational for Institute there is no particular reason for the laws that the same time, cosmology by its very nature is govern our universe. arrogant. The idea that we can understand Quarks and the Cosmos. Michael S. ENKINS Turner in Science, Vol. 315, pages Cosmologists have mixed feelings about the something as vast in both space and time as our 59–61; January 5, 2007.

ADRIANJ multiverse. If the disconnected subuniverses are universe is, on the face of it, preposterous. This

AND truly incommunicado, we cannot hope to test strange mix of humility and arrogance has got- Dark Energy and the Accelerating Universe. Joshua Frieman, Michael S.

FRENK their existence; they seem to lie beyond the realm ten us pretty far in the past century in advancing of science. Part of me wants to scream, One uni- our understanding of the present universe and Turner and Dragan Huterer in Annual

ARLOS Reviews of Astronomy and Astrophys-

, C , verse at a time, please! On the other hand, the its origin. I am bullish on further progress in the

AO ics, Vol. 46, pages 385–432; 2008.

G G G multiverse solves various conceptual problems. coming years, and I firmly believe we are living Available online at arxiv.org/

LIAN If correct, it will make Hubble’s enlargement in a golden age of cosmology. ■ abs/0803.0982

The first step in figuring out how the human mind arose is determining what distinguishes our mental processes from those of other creatures

ot too long ago three aliens descended to Earth to evaluate the status of intelligent life. One specialized in engineering, None in chemistry and one in computation. Turning to his colleagues, the engineer reported (translation follows): “All of the creatures here are solid, some segmented, with capacities to move on the ground, through the water or air. All extremely slow. Unimpressive.” The chemist then commented: “All quite similar, derived from different sequences of four chemical ingredients.” Next the computational expert opined: “Limited computing abilities. But one, the hairless biped, is unlike the others. It exchanges information in a manner that is primitive and inefficient but remarkably different from the others. It creates many odd objects, including ones that are consum- able, others that produce symbols, and yet others that destroy members of its tribe.” Key Concepts “But how can this be?” the engineer mused. “Given the similarity ■ ■ Charles Darwin argued that a in form and chemistry, how can their computing capacity differ?” continuity of mind exists be- “I am not certain,” confessed the computational alien. “But they tween humans and other ani- appear to have a system for creating new expressions that is infinite- mals, a view that subsequent ly more powerful than those of all the other living kinds. I propose scholars have supported. that we place the hairless biped in a different group from the other ) ■ ■ But mounting evidence indi- animals, with a separate origin, and from a different galaxy.” The styling cates that, in fact, a large men- other two aliens nodded, and then all three zipped home to present tal gap separates us from our their report. fellow creatures. Recently the Perhaps our alien reporters should not be faulted for classifying author identified four unique

humans separately from bees, birds, beavers, baboons and bonobos. ); Gene Burkhardt ( aspects of human cognition. After all, our species alone creates soufflés, computers, guns, make- ■ ■ The origin and evolution of up, plays, operas, sculptures, equations, laws and religions. Not only these distinctive mental traits have bees and baboons never made a soufflé, they have never even photoillustration remain largely mysterious, but contemplated the possibility. They simply lack the kind of brain that clues are emerging slowly. has both technological savoir faire and gastronomical creativity.

—The Editors Charles Darwin argued in his 1871 book The Descent of Man holly lindeM ( origin of origin

30 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. www.ScientificAmerican.com © 2009 SCIENTIFIC AMERICAN, INC. SCIENTIFIC AMERICAN 31 that the difference between human and nonhu- KEY INGREDIENTS (“Walkman”) or musical forms, among other man minds is “one of degree and not of kind.” OF THE possibilities. Scholars have long upheld that view, pointing in HUMAN MIND The second distinguishing characteristic of recent years to genetic evidence showing that we the human mind is its capacity for the promiscu- share some 98 percent of our genes with chim- The four traits below distinguish ous combination of ideas. We routinely connect panzees. But if our shared genetic heritage can the human mind from those of thoughts from different domains of knowledge, animals. Uncovering the origin explain the evolutionary origin of the human of the human mind will require allowing our understanding of art, sex, space, mind, then why isn’t a chimpanzee writing this explaining how these unique causality and friendship to combine. From this essay, or singing backup for the Rolling Stones properties came about. mingling, new laws, social relationships and or making a soufflé? Indeed, mounting evidence technologies can result, as when we decide that indicates that, in contrast to Darwin’s theory of Generative computation enables it is forbidden [moral domain] to push someone a continuity of mind between humans and other humans to create a virtually limitless [motor action domain] intentionally [folk psy- variety of words, concepts and species, a profound gap separates our intellect things. The characteristic encompass- chology domain] in front of a train [object do- from the animal kind. This is not to say that our es two types of operation: recursive main] to save the lives [moral domain] of five mental faculties sprang fully formed out of no- and combinatorial. Recursion is the [number domain] others. where. Researchers have found some of the repeated use of a rule to create new Third on my list of defining properties is the building blocks of human cognition in other spe- expressions. The combinatorial use of mental symbols. We can spontaneously operation is the mixing of discrete cies. But these building blocks make up only the — elements to engender new ideas. convert any sensory experience real or imag- cement footprint of the skyscraper that is the hu- ined—into a symbol that we can keep to our- man mind. The evolutionary origins of our cog- Promiscuous combination of ideas selves or express to others through language, art, nitive abilities thus remain rather hazy. Clarity allows the mingling of different music or computer code. is emerging from novel insights and experimen- domains of knowledge—such as art, Fourth, only humans engage in abstract tal technologies, however. sex, space, causality and friendship— thought. Unlike animal thoughts, which are thereby generating new laws, social relationships and technologies. largely anchored in sensory and perceptual expe- Singularly Smart riences, many of ours have no clear connection If we scientists are ever to unravel how the human Mental symbols encode sensory to such events. We alone ponder the likes of uni- mind came to be, we must first pinpoint exactly experiences both real and imagined, corns and aliens, nouns and verbs, infinity and what sets it apart from the minds of other crea- forming the basis of a rich and God. tures. Although humans share the vast majority complex system of communication. Although anthropologists disagree about ex- Such symbols can be kept to of their genes with chimps, studies suggest that oneself or expressed to others as actly when the modern human mind took shape, small genetic shifts that occurred in the human words or pictures. it is clear from the archaeological record that a lineage since it split from the chimp line produced major transformation occurred during a relative- massive differences in computational power. Abstract thought permits contem- ly brief period of evolutionary history, starting This rearranging, deleting and copying of univer- plation of things beyond what we can approximately 800,000 years ago in the Paleo- sal genetic elements created a brain with four spe- see, hear, touch, taste or smell. lithic era and crescendoing around 45,000 to cial properties. Together these distinctive char- 50,000 years ago. It is during this period of the acteristics, which I have recently identified based Paleolithic, an evolutionary eyeblink, that we see on studies conducted in my lab and elsewhere, for the first time multipart tools; animal bones constitute what I term our humaniqueness. punctured with holes to fashion musical instru- The first such trait is generative computation, ments; burials with accoutrements suggesting be- the ability to create a virtually limitless variety of liefs about aesthetics and the afterlife; richly sym- “expressions,” be they arrangements of words, bolic cave paintings that capture in exquisite de- sequences of notes, combinations of actions, or tail events of the past and the perceived future; strings of mathematical symbols. Generative and control over fire, a technology that combines computation encompasses two types of opera- our folk physics and psychology and allowed our tion, recursive and combinatorial. Recursion is ancestors to prevail over novel environments by the repeated use of a rule to create new expres- creating warmth and cooking foods to make sions. Think of the fact that a short phrase can be them edible. embedded within another phrase, repeatedly, to These remnants of our past are magnificent create longer, richer descriptions of our thoughts – reminders of how our forebears struggled to for example, the simple but poetic expression solve novel environmental problems and express from Gertrude Stein: “A rose is a rose is a rose.” themselves in creative new ways, marking their The combinatorial operation, meanwhile, is the unique cultural identities. Nevertheless, the ar- mixing of discrete elements to engender new chaeological evidence will forever remain silent ideas, which can be expressed as novel words on the origins and selective pressures that led to

32 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. GENERATIVE COMPUTATION by humans but not other animals is reflected in tool usage. Unlike other tool-using creatures, which make implements from a single material and for a single purpose, humans routinely combine materials to form tools and often use a given instrument in a number of ways. Here an orangutan employs a single leaf as an umbrella, whereas humans utilize a pencil made of several materials for a variety of purposes.

the four ingredients making up our humanique-

) ness. The gorgeous cave paintings at Lascaux, for instance, indicate that our ancestors understood

);

pencil in hair — ( the dual nature of pictures that they are both objects and refer to objects and events. They do not, however, reveal whether these painters and GettyImages their admirers expressed their aesthetic prefer- writing in notebook ( ences about these artworks by means of symbols Corbis / that were organized into grammatical classes

); Brad); Wilson (nouns, verbs, adjectives) or whether they imagined conveying these ideas equally well through often bizarre, sometimes distasteful, frequently Somos Images Somos [The Author] sound or sign, depending on the health of their incomprehensible and occasionally immoral. ane L

erasing with pencil with erasing sensory systems. Similarly, none of the ancient No other animal exhibits such variation in life- Marc Hauser is a professor of ( instruments that have been found—such as the style. Looked at in this way, a chimpanzee is a psychology, human evolutionary ); Patrick); biology, and organismic and 35,000-year-old flutes made of bone and ivory— cultural nonstarter. evolutionary biology at Harvard tell a story about use, about whether a few notes Chimps and other animals are still interesting orangutan

( University. He studies the evolu- were played over and over again, Philip Glass– and relevant for understanding the origins of the tionary and developmental foun- style, or about whether the composer imagined, human mind, though. In fact, only by working dations of the human mind, with Getty Images/Vico Collective Images/Vico Getty

GettyImages as did Wagner, embedding themes within themes out which capacities we share with other animals the aim of determining which ulin g in a recursive manner. and which are ours alone can scientists hope to mental capacities humans share ra ichael D

m with other animals and which are

ar What we can say with utmost confidence is piece together the story of how our humanique- lin C

A unique to us. ); that all people, from the hunter-gatherers on the ness came to be.

PeteH African savanna to the traders on Wall Street, ); J ); are born with the four ingredients of huma- Beautiful Minds pencil in book ( Hauser niqueness. How these ingredients are added to When my youngest daughter, Sofia, was three

Corbis the recipe for creating culture varies consider- years old, I asked her what makes us think. She ably from group to group, however. Human cul- pointed to her head and said: “My brain.” I then tures may differ in their languages, musical com- asked her whether other animals have brains, Whitehurst Whitehurst m positions, moral norms and artifacts. From the starting with dogs and monkeys and then birds Willia courtesy of lilan hauser ( viewpoint of one culture, another’s practices are and fish. She said yes. When I asked her about the

www.ScientificAmerican.com SCIENTIFIC AMERICAN 33 © 2009 SCIENTIFIC AMERICAN, INC. ant that was crawling in front of us, she said: “No. Too small.” We adults know that size does not provide a litmus test of whether an animal has a brain, although size does affect some aspects of brain structure and, consequently, some aspects of thought. And research has shown that most of the different cell types in the brain, along with their chemical messengers, are the same across vertebrate species, including humans. Furthermore, the general organization of the different structures in the brain’s outermost layer, the cerebral cortex, is largely the same in monkeys, apes and humans. In other words, humans have a number of brain features in common with other species. Where we differ from them is in the relative size of particular regions of the cortex and how these regions connect, differences that give rise to thoughts having no analogue elsewhere in the animal kingdom. Animals do exhibit sophisticated behaviors that appear to presage some of our capabilities. Take, for example, the ability to create or mod- maintaining dominance status, caring for in- ify objects for a particular goal. Male bower- fants, and finding new mates and coalition part- birds construct magnificent architectural ners. Rather they can readily respond to novel structures from twigs and decorate them with social situations, as when a subordinate animal feathers, leaves, buttons and paint made from with a unique skill gains favors from more dom- crushed berries to attract females. New Caledo- inant individuals. Killer whale brain nian crows carve blades into fishing sticks for These observations inspire a sense of wonder 5,620 grams catching insects. Chimpanzees have been ob- at the beauty of nature’s R&D solutions. But served to use wooden spears to shish-kebab bush once we get over this frisson, we must confront babies tucked away in tree crevasses. the gap between humans and other species, a In addition, experimental studies in a number space that is cavernous, as our aliens reported. of animals have revealed a native folk physics To fully convey the extent of this gap and the dif- that enables them to generalize beyond their di- ficulty of deciphering how it arose, let me de- rect experiences to create novel solutions when scribe our humaniqueness in more detail. exposed to foreign challenges in the laboratory. In one such experiment, when orangutans and Minding the Gap Human brain chimps were presented with a mounted plastic One of our most basic tools, the No. 2 pencil, 1,350 grams cylinder containing a peanut at the bottom, they used by every test taker, illustrates the excep- accessed the out-of-reach treat by sipping water tional freedom of the human mind as compared  from their drinking fountains and then spitting with the limited scope of animal cognition. You Etruscan shrew brain the liquid into the cylinder, thus making the pea- hold the painted wood, write with the lead, and 0.1 gram nut float to the top. erase with the pink rubber held in place by a met- Animals also exhibit social behaviors in com- al ring. Four different materials, each with a par- SIZING UP mon with humans. Knowledgeable ants teach ticular function, all wrapped up into a single THE BRAIN their naive pupils by guiding them to essential tool. And although that tool was made for writ- food resources. Meerkats provide their pups ing, it can also pin hair up into a bun, bookmark Humans are smarter than with tutorials on the art of dismembering a le- creatures whose brains are a page or stab an annoying insect. Animal tools, larger than ours in absolute thal but delectable scorpion. And a rash of stud- in contrast—such as the sticks chimps use to fish terms, such as killer whales, as ies have shown that animals as varied as domes- termites out from their mounds—are composed well as those animals whose tic dogs, capuchin monkeys and chimpanzees of a single material, designed for a single func- brains are larger than ours in object to unfair distributions of food, exhibiting tion and never used for other functions. None relative terms (that is, relative to ift

what economists call inequity aversion. What is have the combinatorial properties of the pencil. w body size), such as shrews. Thus, s size alone does not explain the more, ample evidence demonstrates that ani- Another simple tool, the telescopic, collaps- w

uniqueness of the human mind. mals are not locked into their daily routines for ible cup found in many a camper’s gear, provides andre

34 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. an example of recursion in action. To make this device, the manufacturer need only program a simple rule—add a segment of increasing size to the last segment—and repeat it until the desired size is reached. Humans use recursive operations mans are alone, however, in having a system of ANIMALS may use a handful of such as this in virtually all aspects of mental life, linguistic communication that is based on the simple utterances to repre- from language, music and math to the genera- manipulation of mental symbols, with each ex- sent objects and events in the tion of a limitless range of movements with our ample of a symbol falling into a specific and ab- present, but their range of legs, hands and mouths. The only glimmerings stract category such as noun, verb and adjective. expression is very limited compared with that of hu- of recursion in animals, however, have come Although some animals have sounds that appear mans, whose ability to en- from watching their motor systems in action. to represent more than their emotions, convey- gage in abstract thought All creatures are endowed with recursive mo- ing information about objects and events such as additionally enables them to tor machinery as part of their standard operat- food, sex and predation, the range of such discuss not only the future ing equipment. To walk, they put one foot in sounds pales in relation to our own, and none of and past but also abstract front of the other, over and over again. To eat, them falls into the abstract categories that struc- concepts, such as the spiritual they may grasp an object and bring it to the ture our linguistic expressions. teachings of the Dalai Lama. mouth repeatedly until the stomach sends the This claim requires clarification, because it signal to stop. In animal minds, this recursive often elicits extreme skepticism. You might system is locked away in the motor regions of the think, for example, that animal vocabularies brain, closed off to other brain areas. Its exis- appear small because researchers studying their tence suggests that a critical step in acquiring communications do not really understand what our own distinctive brand of thinking was not they are talking about. Although scientists have

) the evolution of recursion as a novel form of much to learn about animal vocalizations, and computation but the release of recursion from its communication more generally, I think insuffi- Dalai Lama Dalai (

motor prison to other domains of thought. How cient study is unlikely to explain the large gap. IS B it was unlocked from this restrictive function Most vocal exchanges between animals consist links to one of our other ingredients —promiscu- of one grunt or coo or scream, with a single vol-

euters/ COR ous interfaces—which I will turn to shortly. ley back. It is possible that animals pack a vast R ); ); The mental gap broadens when we compare amount of information into a 500-millisecond lion ( human language with communication in other grunt—perhaps equivalent to “Please groom my species. Like other animals, humans have a non- lower back now, and I will groom yours later.”

GettyImages verbal communication system that conveys our But then why would we humans have developed emotions and motivations—the chortles and such an arcane and highly verbose system if we rt Wolfert

A cries of little babies are part of this system. Hu- could have solved it all with a grunt or two?

www.ScientificAmerican.com SCIENTIFIC AMERICAN 35 © 2009 SCIENTIFIC AMERICAN, INC. MORE THAN MATH: Many animal Furthermore, even if we grant that the honey- ity to make promiscuous connections between species can count. But only bee’s waggle dance symbolically represents the systems of understanding. Consider the ability humans can calculate the delicious pollen located a mile north and that the to quantify objects and events, a capacity that circumference of the earth, putty-nosed monkey’s alarm calls symbolically we share with other animals. A wide variety of the speed of light or the represent different predators, these uses of sym- species have at least two nonlinguistic abilities likelihood of winning the bols are unlike ours in five essential ways: they for counting. One is precise and limited to num- lottery. In addition, we may are triggered only by real objects or events, nev- bers less than four. The other is unlimited in combine our number system with various other domains er imagined ones; they are restricted to the pres- scope, but it is approximate and limited to cer- of thought, such as morality, ent; they are not part of a more abstract classifi- tain ratios for discrimination—an animal that deciding whether to save five cation scheme, such as those that organize our can discriminate one from two, for instance, can people over one, for instance. words into nouns, verbs and adjectives; they are also discriminate two from four, 16 from 32, rarely combined with other symbols, and when and so on. The first system is anchored in a brain they are, the combinations are limited to a string region involved in keeping track of individuals,

of two, with no rules; and they are fixed to par- whereas the second is anchored in brain regions ) ticular contexts. that compute magnitudes. Human language is additionally remark- Last year my colleagues and I described a able—and entirely different from the communi- third counting system in rhesus monkeys, one woman at blackboard at woman cation systems of other animals —in that it oper- that may help us understand the origins of the (

ates equally well in the visual and auditory human ability to mark the difference between Corbis modes. If a songbird lost its voice and a honey- singular and plural. This system operates when chultz bee its waggle, their communication would end. individuals see sets of objects presented at the S But when a human is deaf, sign language pro- same time—as opposed to individuals presented ichard R vides an equally expressive mode of communi- serially—and causes rhesus monkeys to discrimi- ); cation that parallels its acoustic cousin in struc- nate one from many but not many from many macaque tural complexity. food items. In our experiment, we showed a rhe- ( Our linguistic knowledge, along with the sus monkey one apple and placed it in a box. We

computations it requires, also interacts with oth- then showed the same monkey five apples and GettyImages

er domains of knowledge in fascinating ways placed all five at once into a second box. Given a lach F m i

that strikingly reflect our uniquely human abil- choice the monkey consistently picked the second T

36 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. box with five apples. Then we put two apples in For instance, studies of chimeric animals—in Ivory Bird ScuLpture  one box and five into the other. This time the which brain circuits from an individual of one monkey did not show a consistent preference. We species are transplanted into an individual of an- LIMITED CLUES humans do essentially the same thing when we other species—are helping to unravel how the The archaeological record reveals say “one apple” and “two, five or 100 apples.” brain is wired. And experiments with genetical- that humans were routinely But something peculiar happens when the hu- ly modified animals are revealing genes that play making art and musical instruments by 35,000 years ago, indi- man linguistic system connects up with this more roles in language and other social processes. cating that they were thinking ancient conceptual system. To see how, try this Such achievements do not reveal anything about symbolically by then. But modern exercise: for the numbers 0, 0.2 and –5, add the what our nerve cells do to give us our unique scholars have no way of knowing most appropriate word: “apple” or “apples.” If mental powers, but they do provide a roadmap what these long-ago people you are like most native English speakers, includ- for further exploration of these traits. thought about the symbols they left behind nor how they coming young children, you selected “apples.” In Still, for now, we have little choice but to ad- posed their music. Such artifacts fact, you would select “apples” for “1.0.” If you mit that our mind is very different from that of are thus of limited use in piecing are surprised, good, you should be. This is not a even our closest primate relatives and that we do together the origins of our unique rule we learned in grammar school—in fact, not know much about how that difference came mental abilities. strictly speaking, it is not grammatically correct. to be. Could a chimpanzee think up an experi- But it is part of the universal grammar that we ment to test humans? Could a chimpanzee imag- Bird Bone Flute  alone are born with. The rule is simple but ab- ine what it would be like for us to solve one of stract: anything that is not “1” is pluralized. their problems? No and no. Although chimpan- The apple example demonstrates how differ- zees can see what we do, they cannot imagine ent systems—syntax and concepts of sets—inter- what we think or feel because they lack the req- act to produce new ways of thinking about or uisite mental machinery. Although chimpanzees conceptualizing the world. But the creative pro- and other animals appear to develop plans and cess in humans does not stop here. We apply our consider both past experiences and future op- language and number systems to cases of moral- tions, there is no evidence that they think in ity (saving five people is better than saving one), terms of counterfactuals—imagining worlds economics (if I am giving $10 and offer you $1, that have been against those that could be. We that seems unfair, and you will reject the dollar), humans do this all the time and have done so and taboo trade-offs (in the U.S., selling our chil- ever since our distinctive genome gave birth to dren, even for lots of money, is not kosher). our distinctive minds. Our moral systems are premised on this mental capacity. Alien Thoughts Have our unique minds become as powerful From didactic meerkats to inequity-averse mon- as a mind can be? For every form of human ex- ) keys, the same observation applies: each of these pression—including the world’s languages, mu- animals has evolved an exquisite mind that is sical compositions, moral norms and technolog- bone flute bone ( adapted to singular problems and is thus limited ical forms—I suspect we are unable to exhaust

AP PhotoAP when it comes to applying skills to novel prob- the space of all possibilities. There are significant

lems. Not so for us hairless bipeds. Once in place, limitations to our ability to imagine alternatives. the modern mind enabled our forebears to If our minds face inherent constraints on what

aniel Maurer aniel explore previously uninhabited parts of the they can conceive, then the notion of “thinking ➥

D More To ; ) earth, to create language to describe novel events, outside of the box” is all wrong. We are always Explore and to envision an afterlife. inside the box, limited in our capacity to envision The Faculty of Language: What

bird sculpturebird The roots of our cognitive abilities remain alternatives. Thus, in the same way that chim- (

Is It, Who Has It, and How Did largely unknown, but having pinpointed the panzees cannot imagine what it is like to be hu- It Evolve? Marc D. Hauser, Noam unique ingredients of the human mind, scientists man, humans cannot imagine what it is like to be Chomsky and W. Tecumseh Fitch magazine now know what to look for. To that end, I am an intelligent alien. Whenever we try, we are in Science, Vol. 298, pages 1569–1579; N ature hopeful that neurobiology will prove illuminat- stuck in the box that we call the human mind. November 22, 2002. ing. Although scholars do not yet understand The only way out is through evolution, the revo- Moral Minds: How Nature how genes build brains and how electrical ac lutionary remodeling of our genome and its po- Designed Our Universal Sense tivity in the brain builds thoughts and emotions, tential to sculpt fresh neural connections and of Right and Wrong. Marc D. we are witnessing a revolution in the sciences fashion new neural structures. Such change Hauser. Harper Collins, 2006. of the mind that will fill in these blanks—and would give birth to a novel mind, one that would AP Photo/University of Tübingen/ of Photo/University AP Baboon Metaphysics: The enrich our understanding of why the human look on its ancestors as we often look on ours: Evolution of a Social Mind. Dorothy brain differs so profoundly from those of other with respect, curiosity, and a sense that we are L. Cheney and Robert M. Seyfarth. ildeJensen

H creatures. alone, paragons in a world of simple minds. ■ University of Chicago Press, 2007.

Fresh clues hint at how the first living organisms arose from inanimate matter

very living cell, even the simplest bacterium, teems with molecular contraptions that would be the envy of any nanotech- Enologist. As they incessantly shake or spin or crawl around the cell, these machines cut, paste and copy genetic molecules, shuttle nutrients around or turn them into energy, build and repair cellular membranes, relay mechanical, chemical or electrical messages— the list goes on and on, and new discoveries add to it all the time. It is virtually impossible to imagine how a cell’s machines, which are mostly protein-based catalysts called enzymes, could have formed spontaneously as life first arose from nonliving matter around 3.7 billion years ago. To be sure, under the right conditions some building blocks of proteins, the amino acids, form easily from simpler chemicals, as Stanley L. Miller and Harold C. Urey of the University of Chicago discovered in pioneering experiments in the 1950s. But going from there to proteins and enzymes is a different matter. A cell’s protein-making process involves complex enzymes pull- ing apart the strands of DNA’s double helix to extract the informa- Key Concepts tion contained in genes (the blueprints for the proteins) and translate it into the finished product. Thus, explaining how life began entails ■ ■ Researchers have found a way a serious paradox: it seems that it takes proteins—as well as the in- that the genetic molecule RNA could have formed from chemi- formation now stored in DNA—to make proteins. cals present on the early earth. On the other hand, the paradox would disappear if the first organisms did not require proteins at all. Recent experiments suggest it ■ ■ Other studies have supported would have been possible for genetic molecules similar to DNA or to ) the hypothesis that primitive

its close relative RNA to form spontaneously. And because these mol- styling cells containing molecules similar to RNA could assemble ecules can curl up in different shapes and act as rudimentary catalysts, spontaneously, reproduce and they may have become able to copy themselves —to reproduce —with- evolve, giving rise to all life. out the need for proteins. The earliest forms of life could have been

simple membranes made of fatty acids—also structures known to ); Gene Burkhardt ( ■ ■ Scientists are now aiming at form spontaneously—that enveloped water and these self-replicating creating fully self-replicating artificial organisms in the lab genetic molecules. The genetic material would encode the traits that

oratory—essentially giving life each generation handed down to the next, just as DNA does in all photoillustration a second start to understand things that are alive today. Fortuitous mutations, appearing at ran- how it could have started the dom in the copying process, would then propel evolution, enabling

first time. —The Editors these early cells to adapt to their environment, to compete with one holly lindem ( origin of origin

38 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. www.ScientificAmerican.com SCIENTIFIC AMERICAN © 2009 SCIENTIFIC AMERICAN, INC. 39 [building blocks] another, and eventually to turn into the life- forms we know. First Genetic Molecules The actual nature of the first organisms and the exact circumstances of the origin of life may The first entities on earth DOUBLE-STRANDED RNA be forever lost to science. But research can at capable of reproducing and evolving probably carried least help us understand what is possible. The ul- A their genetic information in timate challenge is to construct an artificial or- some molecule similar to RNA, U ganism that can reproduce and evolve. Creating a close relative of DNA. Both life anew will certainly help us understand how DNA and RNA are chains of life can start, how likely it is that it exists on oth- units called nucleotides (higher worlds and, ultimately, what life is. lighted, left), so a major question is how nucleotides first A Got to Start Somewhere arose from simpler chemicals. U One of the most difficult and interesting myster- The three components of a ies surrounding the origin of life is exactly how nucleotide—a nucleobase, a the genetic material could have formed starting phosphate and a sugar—can each form spontaneously, but from simpler molecules present on the early they do not readily join to- earth. Judging from the roles that RNA has in gether in the right way (cen- G modern cells, it seems likely that RNA appeared ter). Recent experiments, C before DNA. When modern cells make proteins, however, have shown that at they first copy genes from DNA into RNA and least two types of RNA nucle- Sugar then use the RNA as a blueprint to make pro- otides, those containing the Nucleobase teins. This last stage could have existed indepen- nucleobases called C and U, C dently at first. Later on, DNA could have ap could arise through a different peared as a more permanent form of storage, route (far right). (In modern Phosphate thanks to its superior chemical stability. organisms, RNA nucleobases G come in the four types Investigators have one more reason for think- Sugar- A, C, G and U, the letters of ing that RNA came before DNA. The RNA ver- phosphate Complementary the genetic alphabet.) backbone nucleobase pairs sions of enzymes, called ribozymes, also serve a pivotal role in modern cells. The structures that

translate RNA into proteins are hybrid RNA- Meanwhile the phosphate and sugar molecules protein machines, and it is the RNA in them that form the backbone of each strand of DNA or does the catalytic work. Thus, each of our cells RNA. appears to carry in its ribosomes “fossil” evi- What is LIFE? Nucleobases can assemble spontaneously, in le conditions.” le dence of a primordial RNA world. Scientists have long struggled to a series of steps, from cyanide, acetylene and wa- Much research, therefore, has focused on un- define “life” in a way that is broad ter—simple molecules that were certainly present derstanding the possible origin of RNA. Genetic enough to encompass forms not in the primordial mix of chemicals. Sugars are ay 14, 2009

yet discovered. Here are some of plausib iotically molecules such as DNA and RNA are polymers also easy to assemble from simple starting mate- b

the many proposed definitions. ol. 459; M (strings of smaller molecules) made of building rials. It has been known for well over 100 years V blocks called nucleotides. In turn, nucleotides that mixtures of many types of sugar molecules

1. Physicist Erwin Schrödinger Nature, have three distinct components: a sugar, a phos- suggested that a defining can be obtained by warming an alkaline solution phate and a nucleobase. Nucleobases come in of formaldehyde, which also would have been

property of living systems is pre in onucleotides four types and constitute the alphabet in which that they self-assemble against available on the young planet. The problem, utherland,in S the polymer encodes information. In a DNA nu- nature’s tendency toward however, is how to obtain the “right” kind of . disorder, or entropy. D cleotide the nucleobase can be A, G, C or T, sugar—ribose, in the case of RNA—to make nu- standing for the molecules adenine, guanine, cy- cleotides. Ribose, along with three closely related 2. Chemist Gerald Joyce’s tosine or thymine; in the RNA alphabet the let- “working definition,” adopted sugars, can form from the reaction of two sim- ter U, for uracil, replaces the T [see box above]. by NASA, is that life is “a self- pler sugars that contain two and three carbon at- The nucleobases are nitrogen-rich compounds sustaining chemical system oms, respectively. Ribose’s ability to form in that b ri pyrimidine activated of ynthesis that bind to one another according to a simple capable of Darwinian way does not solve the problem of how it became S rule; thus, A pairs with U (or T), and G pairs with evolution.” abundant on the early earth, however, because it owner,Béatrice Gerland andJohn P

C. Such base pairs form the rungs of DNA’s turns out that ribose is unstable and rapidly .

3. In the “cybernetic definition” W twisted ladder— — the familiar double helix and by Bernard Korzeniewski, breaks down in an even mildly alkaline solution. their exclusive pairings are crucial for faithfully life is a network of feedback In the past, this observation has led many re- atthew M y b copying the information so a cell can reproduce. mechanisms. searchers to conclude that the first genetic mole- “ source: swift; andrew

40 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. [building blocks] Some Assembly Required First Genetic Molecules Given that we have at least an outline of potential pathways leading to the nucleobases, sugars FAILED NUCLEOTIDES A NEW ROUTE and phosphate, the next logical step would be to Chemists have long been unable to find a In the presence of phosphate, the raw materials route by which nucleobases, phosphate and for nucleobases and ribose first form 2-amino properly connect these components. This step, ribose (the sugar component of RNA) would oxazole, a molecule that contains part of a sugar however, is the one that has caused the most naturally combine to generate quantities of and part of a C or U nucleobase. Further reac- intense frustration in prebiotic chemistry research RNA nucleotides. tions yield a full ribose-base block and then a full nucleotide. The reactions also produce for the past several decades. Simply mixing the Chemicals present before first living cells “wrong” combinations of the original mole- three components in water does not lead to the cules, but after exposure to ultraviolet rays, only the “right” versions—the nucleotides—survive. spontaneous formation of a nucleotide—largely because each joining reaction also involves the Chemicals present before first living cells release of a water molecule, which does not often occur spontaneously in a watery solution. For the Sugar Nucleobase needed chemical bonds to form, energy must be C supplied, for example, by adding energy-rich compounds that aid in the reaction. Many such 2-aminooxazole compounds may have existed on the early earth. Phosphate Phosphate In the laboratory, however, reactions powered by Arabino- such molecules have proved to be inefficient at x oxazoline best and in most cases completely unsuccessful. This spring—to the field’s great excitement— John Sutherland and his co-workers at the Uni- versity of Manchester in England announced Sugar C that they found a much more plausible way that nucleotides could have formed, which also side- Oxygen steps the issue of ribose’s instability. These cre- Carbon Phosphate ative chemists abandoned the tradition of at- Nitrogen tempting to make nucleotides by joining a nucle- Phosphorus RNA Nucleotide obase, sugar and phosphate. Their approach relies on the same simple starting materials em- cules could not have contained ribose. But one of ployed previously, such as derivatives of cyanide, us (Ricardo) and others have discovered ways in acetylene and formaldehyde. But instead of form- which ribose could have been stabilized. ing nucleobase and ribose separately and then The phosphate part of nucleotides presents trying to join them, the team mixed the start- another intriguing puzzle. Phosphorus—the cen- ing ingredients together, along with phosphate. tral element of the phosphate group—is abun-  JOhn Sutherland of the A complex web of reactions—with phosphate dant in the earth’s crust but mostly in minerals University of Manchester in acting as a crucial catalyst at several steps along England and his collaborators that do not dissolve readily in water, where life the way—produced a small molecule called solved a long-standing question presumably originated. So it is not obvious how 2-aminooxazole, which can be viewed as a frag- in prebiotic chemistry this past phosphates would have gotten into the prebiotic May by demonstrating that ment of a sugar joined to a piece of a nucleobase mix. The high temperatures of volcanic vents can nucleotides can form from [see box above]. convert phosphate-containing minerals to solu- spontaneous chemical reactions. A crucial feature of this small, stable molecule ble forms of phosphate, but the amounts re- He appears below (second from is that it is very volatile. Perhaps small amounts leased, at least near modern volcanoes, are small. left) with members of his lab. of 2-aminooxazole formed together with a mix- A completely different potential source of phosphorus compounds is schreibersite, a mineral commonly found in certain meteors. In 2005 Matthew Pasek and Dante Lauretta of the University of Arizona discovered that the corrosion of schreibersite in water releases its phosphorus component. This pathway seems promising because it releases phosphorus in a

illeret form that is both much more soluble in water V than phosphate and much more reactive with or- aurent

L ganic (carbon-based) compounds.

www.ScientificAmerican.com SCIENTIFIC AMERICAN 41 © 2009 SCIENTIFIC AMERICAN, INC. [FROM MOLECULES TO ORGANISMS] Alternatives ture of other chemicals in a pond on the early to “RNA first” earth; once the water evaporated, the 2-amino ON THE WAY TO LIFE oxazole vaporized, only to condense elsewhere, PNA first: Peptide nucleic acid in a purified form. There it would accumulate as After chemical reactions created the first genetic build- is a molecule with nucleobases ing blocks and other organic molecules, geophysical attached to a proteinlike back- a reservoir of material, ready for further chemi- processes brought them to new environments and bone. Because PNA is simpler and cal reactions that would form a full sugar and nu- concentrated them. The chemicals assembled into more chemically more stable than RNA, cleobase attached to each other. some researchers believe it could complex molecules and then into primitive cells. And Another important and satisfying aspect of have been the genetic polymer of some 3.7 billion years ago geophysics may have also the first life-forms on earth. this chain of reactions is that some of the early- nudged these “protocells”to reproduce. stage by-products facilitate transformations at Metabolism first: Difficulties later stages in of the process. Elegant as it is, in explaining how RNA formed the pathway does not generate exclusively the from inanimate matter have led “correct” nucleotides: in some cases, the sug- some researchers to theorize that ar and nucleobase are not joined in the proper life first appeared as networks of Microscopic layers of clay catalysts processing energy. spatial arrangement. But amazingly, exposure to ultraviolet light—intense solar UV Panspermia: Because “only” a rays hit shallow waters on the early earth —de- few hundred million years divide stroys the “incorrect” nucleotides and leaves be- the formation of the earth and the hind the “correct” ones. The end result is a re- appearance of the first forms of markably clean route to the C and U nucleotides. life, some scientists have suggested that the very first organisms on Of course, we still need a route to G and A, so Nucleotides undergoing earth may have been visitors from challenges remain. But the work by Sutherland’s polymerization other worlds. team is a major step toward explaining how a RNA Breeding GroundS molecule as complex as RNA could have formed In the water solutions in which they formed, nucleotides on the early earth. would have had little chance of combining into long strands able to store genetic information. But under the right conditions—for example, if molecular adhesion Some Warm, Little Vial forces brought them close together between microscopic Once we have nucleotides, the final step in the layers of clay (above)—nucleotides might link up into single strands similar to modern RNA. formation of an RNA molecule is polymerization: the sugar of one nucleotide forms a chemical bond with the phosphate of the next, so that of the origin of life. To be “alive,” organisms nucleotides string themselves together into a must be able to go forth and multiply—a process [The Authors] chain. Once again, in water the bonds do not that includes copying genetic information. In form spontaneously and instead require some modern cells enzymes, which are protein-based, ) Alonso Ricardo, who was born in external energy. By adding various chemicals to carry out this copying function. Cali, Colombia, is a research associ-

a solution of chemically reactive versions of the But genetic polymers, if they are made of the illustration ate at the Howard Hughes Medical Institute at Harvard University. He nucleotides, researchers have been able to pro- right sequences of nucleotides, can fold into com- has a long-standing interest in the duce short chains of RNA, two to 40 nucleotides plex shapes and can catalyze chemical reactions, origin of life and is now studying long. In the late 1990s Jim Ferris and his co- just as today’s enzymes do. Hence, it seems plau- self-replicating chemical systems. workers at the Rensselaer Polytechnic Institute sible that RNA in the very first organisms could ); andrew swift ( Jack W. Szostak is professor of

showed that clay minerals enhance the process, have directed its own replication. This notion has Szostak genetics at Harvard Medical School and Massachusetts General Hospi- producing chains of up to 50 or so nucleotides. inspired several experiments, both at our lab and tal. His interest in the laboratory (A typical gene today is thousands to millions of at David Bartel’s lab at the Massachusetts In uikkonen ( construction of biological struc- nucleotides long.) The minerals’ intrinsic ability stitute of Technology, in which we “evolved” tures as a means of testing our to bind nucleotides brings reactive molecules new ribozymes. understanding of how biology close together, thereby facilitating the formation We started with trillions of random RNA se- works dates back to the artificial chromosomes he described in the of bonds between them [see box above]. quences. Then we selected the ones that had cat- ourtesy of Jussi P ); C November 1987 Scientific The discovery reinforced the suggestion by alytic properties, and we made copies of those. icardo American. some researchers that life may have started on At each round of copying some of the new RNA R mineral surfaces, perhaps in clay-rich muds at the strands underwent mutations that turned them bottom of pools of water formed by hot springs into more efficient catalysts, and once again we

[see “Life’s Rocky Start,” by Robert M. Hazen; singled those out for the next round of copying. lonso ricardo ( Scientific American, April 2001]. By this directed evolution we were able to pro- Certainly finding out how genetic polymers duce ribozymes that can catalyze the copying of

first arose would not by itself solve the problem relatively short strands of other RNAs, although courtesy of A

Cold side of pond Warm side of pond ●4 Membrane incorporates new ●5 Protocell fatty molecules divides, and and grows ASSiSteD reproDuction daughter cells D once released from clay, the newly repeat the cycle ire cti on formed polymers might become engulfed o f in water-fi lled sacs as fatty acids sponta- co n v neously arranged themselves into mem- e c t branes. These protocells probably re- io quired some external prodding to begin n duplicating their genetic material and thus reproducing. In one possible scenar- Daughter io (right), the protocells circulated cells between the cold and warm sides of a pond, which may have been partially Fatty frozen on one side (the early earth was molecules mostly cold) and thawed on the other side by the heat of a volcano. on the cold side, single RNA strands 1 Nucleotides ●1 acted as templates on which new ● Nucleotides nucleotides formed base pairs (with As enter and form pairing with Us and Cs with Gs), resulting complementary strand ●3 Heat separates in double strands ●2 . on the hot side, the strands heat would break the double strands apart ●3 . Membranes could also slowly grow ●4 until the protocells divided into “daughter” protocells ●5 , which could then start the cycle again. RNA once reproduction cycles got going, double evolution kicked in—driven by random strand mutations—and at some point the ●2 Protocell protocells gained the ability to reaches reproduce on their own. life was born. “maturity”

they fall far short of being able to copy polymers the first step to full replication: with their own sequences into progeny RNAs. once a double strand had formed, separation of Recently the principle of R NA self-replication the strands would allow the complement to serve received a boost from Tracey Lincoln and Gerald as a template for copying the original strand. Joyce of the Scripps Research Institute, who With standard DNA or RNA, the process is ex- lIPID MEMBRANEs self-assemble evolved two RNA ribozymes, each of which ceedingly slow. But small changes to the chemi- from fatty acid molecules dis- could make copies of the other by joining togeth- cal structure of the sugar component—changing solved in water. The membranes er two shorter RNA strands. Unfortunately, suc- one oxygen-hydrogen pair to an amino group start out spherical and then cess in the experiments required the presence of (made of nitrogen and hydrogen)—made grow fi laments by absorbing preexisting RNA pieces that were far too long the polymerization hundreds of times faster, so new fatty acids (micrograph and complex to have accumulated spontaneous- that complementary strands formed in hours in- below). They become long, thin ly. Still, the results suggest that RNA has the raw stead of weeks. The new polymer behaved much tubes and break up into many catalytic power to catalyze its own replication. like classic RNA despite having nitrogen-phos- smaller spheres. The fi rst proto- Is there a simpler alternative? We and others phorus bonds instead of the normal oxygen- cells may have divided this way. are now exploring chemical ways of copying ge- phosphorus bonds. vol. 131, no. 15; april 22, 2009 netic molecules without the aid of catalysts. In recent experiments, we started with single, “tem- Boundary Issues plate” strands of DNA. (We used DNA because If we assume for the moment that the gaps in Growing fi lament it is cheaper and easier to work with, but we our understanding of the chemistry of life’s could just as well have used RNA.) We mixed the origin will someday be fi lled, we can begin to templates in a solution containing isolated nucle- consider how molecules might have interact- Membrane otides to see if nucleotides would bind to the tem- ed to assemble into the fi rst cell-like struc- plate through complementary base pairing (A tures, or “protocells.” joining to T and C to G) and then polymerize, The membranes that envelop all modern cells JOurNaL OF tHe aMerICaN CHeMICaL SOCIetY, from “coupled Growth and division of model protocell memBranes,” By tinG f. Zhu and Jack w. sZostak, in thus forming a full double strand. This would be consist primarily of a lipid bilayer: a double sheet

Journey ●2 rnA cAtAlyStS  Ribozymes—folded RNA molecules e t to the Energy s analogous to protein-based en- a Double- Lipid stranded membrane zymes—arise and take on such jobs W Modern RNA as speeding up reproduction and strengthening the protocell’s mem- Cell brane. Consequently, protocells Ribozyme N begin to reproduce on their own. u tr After life got started, com- ie n t petition among life-forms s fueled the drive toward ever more complex organisms. RNA is We may never know the duplicated exact details of early evolu- New tion, but here is a plausible ●1 eVolution StArtS  strand 3  sequence of some of the The fi rst protocell is just a sac ● metABoliSm BeGinS other ribozymes catalyze metabo- major events that led from of water and RNA and requires an Ribozyme external stimulus (such as cycles lism—chains of chemical reactions the fi rst protocell to DNA- of heat and cold) to reproduce. that enable protocells to tap into based cells such as bacteria. But it will soon acquire new traits. nutrients from the environment.

of such oily molecules as phospholip- active versions of nucleotides. The ids and cholesterol. Membranes keep a nucleotides crossed the membrane spon- cell’s components physically together and form taneously and, once inside the model protocell, a barrier to the uncontrolled passage of large lined up on the DNA strand and reacted with one molecules. Sophisticated proteins embedded another to generate a complementary strand. in the membrane act as gatekeepers and pump The experiment supports the idea that the fi rst molecules in and out of the cell, while other pro- protocells contained R NA (or something similar teins assist in the construction and repair of the to it) and little else and replicated their genetic membrane. How on earth could a rudimentary material without enzymes. protocell, lacking protein machinery, carry out these tasks? Let There Be Division Primitive membranes were probably made of For protocells to start reproducing, they would simpler molecules, such as fatty acids (which are have had to be able to grow, duplicate their genet- one component of the more complex phospho- ic contents and divide into equivalent “daughter” lipids). Studies in the late 1970s showed that cells. Experiments have shown that primitive ves- membranes could indeed assemble spontaneous- icles can grow in at least two distinct ways. In ly from plain fatty acids, but the general feeling pioneering work in the 1990s, Pier Luigi Luisi was that these membranes would still pose a for- and his colleagues at the Swiss Federal Institute midable barrier to the entry of nucleotides and of Technology in Zurich added fresh fatty acids other complex nutrients into the cell. This no- to the water surrounding such vesicles. In re - tion suggested that cellular metabolism had to sponse, the membranes incorporated the fatty LiFE, rEDUX develop fi rst, so that cells could synthesize nu- acids and grew in surface area. As water and dis- cleotides for themselves. Work in our lab has solved substances slowly entered the interior, the scientists who study the origin of shown, however, that molecules as large as nu- life hope to build a self-replicat- cell’s volume also increased. ing organism from entirely artifi - cleotides can in fact easily slip across membranes A second approach, which was explored in cial ingredients. The biggest as long as both nucleotides and membranes are our lab by then graduate student Irene Chen, in- challenge is to fi nd a genetic simpler, more “primitive” versions of their mod- volved competition between protocells. Model molecule capable of copying itself ern counterparts. protocells fi lled with RNA or similar materials autonomously. The authors and This fi nding allowed us to carry out a simple their collaborators are designing became swollen, an osmotic effect resulting and synthesizing chemically experiment modeling the ability of a protocell to from the attempt of water to enter the cell and modifi ed versions of RNA and copy its genetic information using environmen- equalize its concentration inside and outside. DNA in the search for this elusive tally supplied nutrients. We prepared fatty acid– The membrane of such swollen vesicles thus property. RNA itself is probably based membrane vesicles containing a short piece came under tension, and this tension drove not the solution: its double of single-stranded DNA. As before, the DNA growth, because adding new molecules relaxes strands, unless they are very short, do not easily separate to was meant to serve as a template for a new strand. the tension on the membrane, lowering the en-

become ready for replication. Next, we exposed these vesicles to chemically re- ergy of the system. In fact, swollen vesicles grew andrew swift

44 Scientific AmericAn September 2009 © 2009 SCIENTIFIC AMERICAN, INC. Amino acid chain DNA ●5 PRoTEINs TAkE oVER  Proteins take on a wide range of tasks within the cell. Protein-based Ribosome catalysts, or enzymes, gradually Ribozymes replace most ribozymes. Enzymes

Folded Folded protein protein

e t Energy s a

●4 PRoTEINs APPEAR  Enzyme N Complex systems of RNA cata- u ●6 THE BIRTH oF DNA  ●7 BACTERIAl WoRlD  t r ie lysts begin to translate strings n other enzymes begin to make DNA. organisms resembling modern t of RNA letters (genes) into s Thanks to its superior stability, bacteria adapt to living virtually chains of amino acids (proteins). DNA takes on the role of primary everywhere on earth and rule Proteins later prove to be more genetic molecule. RNA’s main role unopposed for billions of years, effi cient catalysts and able to Membrane is now to act as a bridge between until some of them begin to evolve carry out a variety of tasks. protein DNA and proteins. into more complex organisms.

by stealing fatty acids from relaxed neighboring er). There could be pools of cold water, perhaps vesicles, which shrank. partly covered by ice but kept liquid by hot rocks. In the past year Ting Zhu, a graduate student The temperature differences would cause con- in our lab, has observed the growth of model vection currents, so that every now and then pro- protocells after feeding them fresh fatty acids. tocells in the water would be exposed to a burst To our amazement, the initially spherical vesi- of heat as they passed near the hot rocks, but they cles did not grow simply by getting larger. In- would almost instantly cool down again as the stead they fi rst extended a thin fi lament. Over heated water mixed with the bulk of the cold wa- about half an hour, this protruding fi lament ter. The sudden heating would cause a double he- grew longer and thicker, gradually transforming lix to separate into single strands. Once back in the entire initial vesicle into a long, thin tube. the cool region, new double strands—copies of This structure was quite delicate, and gentle the original one —could form as the single strands ➥ MorE to shaking (such as might occur as wind generates acted as templates [see box on page 43]. EXPLorE waves on a pond) caused it to break into a num- As soon as the environment nudged protocells synthesizing life. Jack Szostak, ber of smaller, spherical daughter protocells, to start reproducing, evolution kicked in. In par- David P. Bartel and P. Luigi Luisi in which then grew larger and repeated the cycle ticular, at some point some of the RNA sequenc- Nature, Vol. 409, pages 387–390; [see micrograph on page 43]. es mutated, becoming ribozymes that sped up the January 2001. Given the right building blocks, then, the for- copying of RNA—thus adding a competitive ad- Genesis: The scientifi c Quest mation of protocells does not seem that diffi cult: vantage. Eventually ribozymes began to copy for life’s origins. Robert M. Hazen. membranes self-assemble, genetic polymers RNA without external help. Joseph Henry, 2005. self-assemble, and the two components can be It is relatively easy to imagine how RNA- brought together in a variety of ways, for exam- based protocells may have then evolved [see box The RNA World. Edited by Raymond ple, if the membranes form around preexisting above]. Metabolism could have arisen gradually, F. Gesteland, Thomas R. Cech and John F. Atkins. Third edition. Cold polymers. These sacs of water and RNA will as new ribozymes enabled cells to synthesize nu- Spring Harbor Laboratory Press, 2006. also grow, absorb new molecules, compete for trients internally from simpler and more abun- nutrients, and divide. But to become alive, they dant starting materials. Next, the organisms A simpler origin for life. would also need to reproduce and evolve. In par- might have added protein making to their bag of Robert Shapiro in Scientiﬁ c American, ticular, they need to separate their RNA double chemical tricks. Vol. 296, No. 6, pages 24–31; June 2007. strands so each single strand can act as a tem- With their astonishing versatility, proteins plate for a new double strand that can be handed would have then taken over RNA’s role in assist- A New Molecule of life? down to a daughter cell. ing genetic copying and metabolism. Later, the Peter Nielsen in Scientiﬁ c American, This process would not have started on its organisms would have “learned” to make DNA, Vol. 299, No. 6, pages 36–43; own, but it could have with a little help. Imagine, gaining the advantage of possessing a more ro- December 2008. for example, a volcanic region on the otherwise bust carrier of genetic information. At that point, Exploring life’s origins. Multime- cold surface of the early earth (at the time, the the RNA world became the DNA world, and life dia project at the Museum of Science. sun shone at only 70 percent of its current pow- as we know it began. ■ http://exploringorigins.org

The information age began with the realization that machines could emulate the power of minds

n the standard story, the computer’s evolution has been brisk and short. It starts with the giant machines warehoused in World War III–era laboratories. Microchips shrink them onto desktops, Moore’s Law predicts how powerful they will become, and Micro- soft capitalizes on the software. Eventually small, inexpensive devices appear that can trade stocks and beam video around the world. That is one way to approach the history of computing—the history of solid-state electronics in the past 60 years. But computing existed long before the transistor. Ancient astronomers developed ways to predict the motion of the heavenly bodies. The Greeks deduced the shape and size of Earth. Taxes were summed; distances mapped. Always, though, computing was a human pursuit. It was arithmetic, a skill like reading or writing that helped a person make sense of the world. The age of computing sprang from the abandonment of this lim- Key Concepts itation. Adding machines and cash registers came first, but equally critical was the quest to organize mathematical computations using ■ ■ The first “computers” what we now call “programs.” The idea of a program first arose in were people—individuals and teams who would the 1830s, a century before what we traditionally think of as the tediously compute sums by birth of the computer. Later, the modern electronic computers that hand to fill in artillery tables. came out of World War II gave rise to the notion of the universal

computer—a machine capable of any kind of information process- ) ■ ■ Inspired by the work of a com-

ing, even including the manipulation of its own programs. These are styling puting team in revolutionary France, Charles Babbage, a the computers that power our world today. Yet even as computer British mathematician, created technology has matured to the point where it is omnipresent and the first mechanical device that seemingly limitless, researchers are attempting to use fresh insights

could organize calculations. from the mind, biological systems and quantum physics to build ); Gene Burkhardt ( wholly new types of machines. ■ ■ The first modern computers arrived in the 1950s, as

researchers created machines The Difference Engine photoillustration that could use the result In 1790, shortly after the start of the French Revolution, Napoleon of their calculations to alter Bonaparte decided that the republic required a new set of maps to

their operating instructions. establish a fair system of property taxation. He also ordered a switch holly lindeM ( origin of origin

46 Scientific American September 2009 © 2009 SCIENTIFIC AMERICAN, INC. www.ScientificAmerican.com SCIENTIFIC AMERICAN 47 © 2009 SCIENTIFIC AMERICAN, INC. from the old imperial system of measurements ect. It was grunt work, demanding no special to the new metric system. To aid the engineers skills above basic numeracy and literacy. In fact, and mathematicians making the change, the most computers were hairdressers who had lost French ordinance survey offi ce commissioned a their jobs—aristocratic hairstyles being the sort fresh set of mathematical tables. of thing that could endanger one’s neck in revo- In the 18th century, however, computations lutionary France. were done by hand. A “factory fl oor” of be- The project took about 10 years to complete, tween 60 and 80 human computers added and but by then the war-torn republic did not have the subtracted numbers to fi ll in line after line of the funds necessary to publish the work. The manu- tables for the survey’s Tables du Cadastre proj- script languished in the Académie des Sciences

The Difference engine

GeArS OF CHAnGe: Charles Babbage produced a functioning prototype of his Difference engine (left and detail above) in 1832. Al- though it demonstrated the feasibilty of his idea, it was too small to be of practical use. The fi rst full version of a working Difference engine would not be built until 1991, 159 years later, by the london Science Museum, which was guided by Babbage’s detailed design notes. ); DifferenceEngine ) inset Courtesy of the sCienCe MuseuM ( sCienCe MuseuM/ssPl (

48 Scientific AmericAn September 2009 © 2009 SCIENTIFIC AMERICAN, INC. for decades. Then, in 1819, a young British math- not until the 1970s, well into the computer age, TeamWork ematican named Charles Babbage would view it that scholars studied these papers for the first on a visit to Paris. Babbage was 28 at the time; time. The Analytical Engine was, as one of those three years earlier he had been elected to the Roy- scholars remarked, almost like looking at a com- al Society, the most prominent scientific organi- puter designed on another planet. zation in Britain. He was also very knowledgeable about the world of human computers—at The Dark Ages various times he personally supervised the con- Babbage’s vision, in essence, was digital com- struction of astronomical and actuarial tables. puting. Like today’s devices, such machines On his return to England, Babbage decided manipulate numbers (or digits) according to a he would replicate the French project not with set of instructions and produce a precise numer- human computers but with machinery. England ical result. at the time was in the throes of the Industrial Yet after Babbage’s failure, computation en- The Harvard Observatory’s human computers, seen here circa 1890, Revolution. Jobs that had been done by human tered what English mathematician L. J. Comrie examined hundreds of thousands or animal labor were falling to the efficiency of called the Dark Age of digital computing—a pe- of photographic plates between the machine. Babbage saw the power of mecha- riod that lasted into World War II. During this the 1880s and the 1920s, nization and realized that it could replace not time, machine computation was done primarily classifying stars based on color, just muscle but the work of minds. with so-called analog computers. These devices position and brightness. He proposed the construction of his Calcu- model a system using a mechanical analog. Sup- lating Engine in 1822 and secured government pose, for example, one wanted to predict the funding in 1824. For the next decade he im- time of a solar eclipse. To do this digitally, one mersed himself in the world of manufacturing, would numerically solve Kepler’s laws of mo- seeking the best technologies with which to con- tion. Before digital computers, the only practi- struct his engine. cal way to do this was hand computation by hu- The year 1832 was Babbage’s annus mirabi- man computers. (From the 1890s to the 1940s lis. That year he not only produced a function- the Harvard Observatory employed just such a ing model of his calculating machine (which he group of all-female computers.) One could also called the Difference Engine) but also published create an analog computer, a model solar system his classic Economy of Machinery and Manu- made of gears and shafts that would “run” time factures, establishing his reputation as the into the future [see box on next page]. world’s leading industrial economist. He held Before World War II, the most important an- Saturday evening soirees at his home in Dorset alog computing instrument was the Differential Street in London, which were attended by the Analyzer, developed by Vannevar Bush at the

); front rank of society. At these gatherings the Massachusetts Institute of Technology in 1929. model Difference Engine was placed on display At that time, the U.S. was investing heavily in [The Author] as a conversation piece. rural electrification, and Bush was investigating human computers human A year later Babbage abandoned the Differ- electrical transmission. Such problems could be ence Engine for a grander vision that he called encoded in ordinary differential equations, but

servatory ( the Analytical Engine. Whereas the Difference these were very time-consuming to solve. The

e Ob Engine had been limited to the single task of ta- Differential Analyzer allowed for an approxi- g ble making, the Analytical Engine would be ca- mate solution without any numerical process- pable of any mathematical calculation. Like a ing. The machine was physically quite large—it

arvard Colle modern computer, it would have a processor filled a laboratory—and was something of a that performed arithmetic (the “mill”), memory Rube Goldberg construction of gears and rotat- hs at H p to hold numbers (the “store”), and the ability to ing shafts. To “program” the machine, research- Martin Campbell-Kelly is a ra g alter its function via user input, in this case by ers connected the various components of the professor in the department of ) punched cards. In short, it was a computer con- device using screwdrivers, spanners and lead computer science at the University al Photo author

c of Warwick in England, where he i

m ceived in Victorian technology. hammers. Though laborious to set up, once

elly ( specializes in the history of com- K Babbage’s decision to abandon the unfinished done the apparatus could solve in minutes equa- puting. He is author of Computer: ell- strono Difference Engine was not well received, how- tions that would take several days by hand. A A History of the Information mpb ever, and the government demurred to supply dozen copies of the machine were built in the Machine (along with William him with additional funds. Undeterred, he pro- U.S. and England. Aspray) and of From Airline Reser- vations to Sonic the Hedgehog: duced thousands of pages of detailed notes and One of these copies belonged to the U.S. Ar- A History of the Software Industry. machine drawings in the hope that the govern- my’s Aberdeen Proving Ground in Maryland, He is editor of The Works of Courtesy of Curator of A Courtesy of Martin Ca ment would one day fund construction. It was the facility responsible for readying field weap- Charles Babbage.

www.ScientificAmerican.com SCIENTIFIC AMERICAN 49 © 2009 SCIENTIFIC AMERICAN, INC. ons for deployment. To aim artillery at a target tained about 3,000 entries. Even with the Dif- of known range, soldiers had to set the vertical ferential Analyzer, the backlog of calculations and horizontal angles (the elevation and azi- at Aberdeen was mounting. muth) of the barrel so that the fi red shell would Eighty miles up the road from Aberdeen, the follow the desired parabolic trajectory—soaring Moore School of Electrical Engineering at the skyward before dropping onto the target. They University of Pennsylvania had its own differ- selected the angles out of a fi ring table that con- ential analyzer. In the spring of 1942 a 35-year- tained numerous entries for various target dis- old instructor at the school named John W. tances and operational conditions. Mauchly had an idea for how to speed up calcu- Every entry in the fi ring table required the in- lations: construct an “electronic computor” tegration of an ordinary differential equation. [sic] that would use vacuum tubes in place of the A human computer would take two to three mechanical components. Mauchly, a theoreti- days to do each calculation by hand. The Dif- cally-minded individual, found his complement ferential Analyzer, in contrast, would need only in an energetic young researcher at the school about 20 minutes. named J. Presper (“Pres”) Eckert, who had already shown sparks of engineering genius. Everything Is Change On December 7, 1941, Japanese forces attacked the U.S. Navy base at Pearl Harbor. The U.S. was at war. Mobilization meant the army needed ever more fi ring tables, each of which con-

The Analog Computer

SeeInG STArS: An example of the analog computer is the planetarium projector, which is designed to produce a physical analog of the motion of the stars and planets. The Adler planetarium in Chicago installed the fi rst American example in 1930 (left). Although the projectors are not accurate enough for practical computing, the planetarium still thrives. The latest projectors can be seen at new york City’s Hayden planetarium (above) . ) inset ( ); Zeiss projector Zeiss American Museum of Natural History Natural of Museum American Courtesy of the adler PlanetariuMCourtesyfinnin d. of (

A year after Mauchly made his original proposal, following various accidental and bureau- cratic delays, it found its way to Lieutenant Her- man Goldstine, a 30-year-old Ph.D. in mathematics from the University of Chicago who was the technical liaison officer between Aberdeen and the Moore School. Within days Goldstine got the go-ahead for the project. Construction of the ENIAC—for Electronic Numerical Inte- grator and Computer—began on April 9, 1943. It was Eckert’s 23rd birthday. Many engineers had serious doubts about whether the ENIAC would ever be successful. Conventional wisdom held that the life of a vacuum tube was about 3,000 hours, and the ENIAC’s initial design called for 5,000 tubes. At that failure rate, the machine would not function for more than a few minutes before a broken tube put it out of action. Eckert, howev- matical prodigy who tore through his educa- power on: Computing entered er, understood that the tubes tended to fail un- tion. By 23 he had become the youngest ever the electronic age with the der the stress of being turned on or off. He knew privatdozent (the approximate equivalent of an ENIAC, invented by J. Presper it was for that reason radio stations never turned associate professor) at the University of Berlin. Eckert and John W. Mauchly of the Moore School of Electrical off their transmission tubes. If tubes were oper- In 1930 he emigrated to the U.S., where he Engineering at the University of ated significantly below their rated voltage, they joined Albert Einstein and Kurt Gödel as one of Pennsylvania. The ENIAC used would last longer still. (The total number of first faculty members of the Institute for Ad- vacuum tubes to hold numbers tubes would grow to 18,000 by the time the ma- vanced Study in Princeton, N.J. He became a in storage and consumed 150 chine was complete.) naturalized U.S. citizen in 1937. kilowatts of power, equivalent Eckert and his team completed the ENIAC in Von Neumann quickly recognized the power to more than 1,000 modern PCs. two and a half years. The finished machine was of electronic computation, and in the several an engineering tour de force, a 30-ton behe- months after his visit to Aberdeen, he joined in moth that consumed 150 kilowatts of power. meetings with Eckert, Mauchly, Goldstine and The machine could perform 5,000 additions per Arthur Burks—another Moore School instruc- second and compute a trajectory in less time tor—to hammer out the design of a successor than a shell took to reach its target. It was also machine, the Electronic Discrete Variable Auto- a prime example of the role that serendipity of- matic Computer, or EDVAC. ten plays in invention: although the Moore The EDVAC was a huge improvement over School was not then a leading computing re- the ENIAC. Von Neumann introduced the ideas search facility, it happened to be in the right lo- and nomenclature of Warren McCullough and cation at the right time with the right people. Walter Pitts, neuroscientists who had developed Yet the ENIAC was finished in 1945, too late a theory of the logical operations of the brain to help in the war effort. It was also limited in (this is where we get the term computer “mem- its capabilities. It could store only up to 20 num- ory”). Like von Neumann, McCullough and bers at a time. Programming the machine took Pitts had been influenced by theoretical studies days and required manipulating a patchwork of in the late 1930s by British mathematician Alan cables that resembled the inside of a busy tele- Turing, who established that a simple machine phone exchange. Moreover, the ENIAC was de- can be used to execute a huge variety of complex The Analytical signed to solve ordinary differential equations. tasks. There was a collective shift in perception Engine was Some challenges—notably, the calculations re- around this time from the computer as a math- quired for the Manhattan Project—required the ematical instrument to a universal information- almost like solution of partial differential equations. processing machine. John von Neumann was a consultant to the Von Neumann thought of the machine as looking at IS B Manhattan Project when he learned of the having five core parts:Memory held not just nu- a computer OR ENIAC on a visit to Aberdeen in the summer of merical data but also the instructions for opera- designed on

m ann/C 1944. Born in 1903 into a wealthy Hungarian tion. An arithmetic unit performed calcula-

Bett banking family, von Neumann was a mathe- tions. An input “organ” enabled the transfer of another planet.

www.ScientificAmerican.com SCIENTIFIC AMERICAN 51 © 2009 SCIENTIFIC AMERICAN, INC. © 2009 SCIENTIFIC AMERICAN, INC. THe FUTUre programs and data into memory, and an output er—originally designed for mathematical calcu- oF CompUTer organ recorded the results of computation. Fi- lations—turned out to be infi nitely adaptable to arCHITeCTUre nally, a control unit coordinated operations . different uses, from business data processing to This layout, or architecture, makes it possi- personal computing to the construction of a The stored-program computer ble to change the computer’s program without global information network. has formed the basis of comput- altering the physical structure of the machine. We can think of computer development as ing technology since the 1950s. What may come next? Moreover, a program could manipulate its own instructions. This feature would not only enable QuAnTuM: The much touted quan- von Neumann to solve his partial differential tum computer exploits the ability of a equations, it would confer a powerful fl exibility particle to be in many states at once. that forms the very heart of computer science. Quantum computations operate on In June 1945 von Neumann wrote his classic all these states simultaneously. First Draft of a Report on the EDVAC on behalf of the group. In spite of its unfi nished status, it neurAl neT: These systems are formed from many simple processing was rapidly circulated among the computing co- nodes that connect to one another in gnoscenti with two consequences. First, there unique ways. The system as a whole never was a second draft. Second, von Neu- exhibits complex global behavior. mann ended up with most of the credit. lIVInG: Computers based on strands of DNA or RNA process data encoded Machine Evolution in genetic material. The subsequent 60-year diffusion of the computer within society is a long story that has to be told in another place. Perhaps the single most remarkable development was that the comput-

CHAnGInG prOGrAMS: The fi rst practical stored- The Stored-program Computer program computer was the eDSAC, built at the university of Cambridge by Maurice Wilkes and William renwick in 1949 (below). early attempts to make a symbolic programming system (above) were a breakthrough in simplifying programming. ) inset ); sourCe: “the edsaC siMulator ProGraM doCuMentation,” EDSAC PoPPerfoto/Getty iMaGes ( iMaGes PoPPerfoto/Getty By the dePartMent of CoMPuter sCienCe, university of WarWiCk (

52 Scientific AmericAn September 2009 © 2009 SCIENTIFIC AMERICAN, INC. having taken place along three vectors—hardware, software and architecture. The improvements in hardware over the past 60 years are legendary. Bulky electronic tubes gave way in the late 1950s to “discrete” transistors —that is, single transistors individually soldered into place. In the mid-1960s microcircuits contained several transistors—then hundreds of transistors, then thousands of transistors—on a silicon “chip.” The microprocessor, developed in the early 1970s, held a complete computer processing unit on a chip. The microprocessor gave rise to the PC and now controls devices ranging from sprinkler systems to ballistic missiles. The challenges of software were more subtle. In 1947 and 1948 von Neumann and Goldstine produced a series of reports called Planning and Coding Problems for an Electronic Computing 1945. The situation mirrors that of the gasoline- Child’s play: Simple programming languages such as Basic Instrument. In these reports they set down doz- powered automobile—the years have seen many allowed the power of program- ens of routines for mathematical computation technical refinements and efficiency improve- ming to spread to the masses. with the expectation that some lowly “coder” ments in both, but the basic design is largely the A young Paul Allen (seated) and would be able to convert them into working same. And although it might be possible to de- his friend Bill Gates worked on programs. It was not to be. The process of writ- sign a radically better device, both have achieved a Teletype terminal attached by ing programs and getting them to work was ex- what historians of technology call “closure.” In- a phone line to a mainframe cruciatingly difficult. The first to make this dis- vestments over the decades have produced such computer that filled a room. covery was Maurice Wilkes, the University of excellent gains that no one has had a compelling Cambridge computer scientist who had created reason to invest in an alternative [see “Internal- EDSAC, the first practical stored-program com- Combustion Engine,” on page 77]. puter [see box on opposite page]. In his Mem- Yet there are multiple possibilities for radical oirs, Wilkes ruefully recalled the moment in evolution. In the 1980s interest ran high in so- 1949 when “the realization came over me with called massively parallel machines, which con- full force that a good part of the remainder of tained thousands of computing elements oper- my life was going to be spent in finding errors in ating simultaneously. This basic architecture is my own programs.” still used for computationally intensive tasks He and others at Cambridge developed a such as weather forecasting and atomic weap- method of writing computer instructions in a ons research. Computer scientists have also symbolic form that made the whole job easier looked to the human brain for inspiration. We and less error prone. The computer would take now know that the brain contains specialized this symbolic language and then convert it into processing centers for different tasks, such as binary. IBM introduced the programming lan- face recognition or speech understanding. Sci- guage Fortran in 1957, which greatly simplified entists are harnessing some of these ideas in the writing of scientific and mathematical pro- “neural networks” for applications such as li- ➥ More To grams. At Dartmouth College in 1964, educa- cense plate identification and iris recognition. Explore tor John G. Kemeny and computer scientist More blue sky research is focused on build- The Difference Engine: Charles Thomas E. Kurtz invented Basic, a simple but ing computers from living matter such as DNA Babbage and the Quest to Build mighty programming language intended to de- [see “Bringing DNA Computers to Life,” by the First Computer. Doron Swade. mocratize computing and bring it to the entire Ehud Shapiro and Yaakov Benenson; Scientif- Penguin, 2002. undergraduate population. With Basic even ic American, May 2006] and computers that Computer: A History of the Infor- schoolkids—the young Bill Gates among them — harness the weirdness of the quantum world hool mation Machine. Martin Campbell- could begin to write their own programs. [see “The Limits of Quantum Computers,” by Kelly and William Aspray. Westview In contrast, computer architecture—that is, Scott Aaronson; Scientific American, March Press, 2004. akeside Sc the logical arrangement of subsystems that 2008]. No one knows what the computers of 50 The Modern History of Comput- make up a computer—has barely evolved. Near- years hence will look like. Perhaps their abilities ing. Stanford Encyclopedia of Philoso- ly every machine in use today shares its basic ar- will surpass even the powers of the minds that phy. http://plato.stanford.edu/

Courtesy of the L chitecture with the stored-program computer of created them. ■ entries/computing-history

The Start of Everything here do rainbows come from, Daddy? After exploring the big questions in the articles that precede What about flying cars—and LSD? this section—the origins of the universe and the beginnings of life WIn the beginning, there was always the toddler's query, itself—we now turn to everything else. The origins of external ears, which led to the schoolchild's raised hand and, still later, the engi- Scotch tape, the ethereal evolution of love and even artificial hearts neer's back-of-the envelope sketch of a new invention. are revealed in the pages that follow. Everything started somewhere—and someone had to ask. Think Of course, many of you were wondering what came before the of what you are about to read as a collection of queries rooted in big bang. But others ponder an even more urgent question. Read on, childlike curiosity about the world around us and the still larger and you may find out who or what prevailed in the contest between universe that stretches beyond. the chicken and the ovum. —The Editors

Rainbows The simple magic of their shape and colors still puzzles

nglish poet John Keats famously worried that scientific explana- spheric physicist Craig Bohren of Pennsylvania State University. tions would “unweave a rainbow”—that by elucidating rain- The central principle is that each water droplet in the air acts as a Ebows and other phenomena rationally, scientists would drain mirror, lens and prism, all in one. Droplets scatter sunlight in every the world of its mystery. Yet if anything, the close study of rainbows direction but do so unevenly, tending to focus light 138 degrees from enriches our appreciation of them. The multicolored arc is just the the incident direction. Those droplets that form this angle with the sun beginning. Look closely, and you will see that outside the main bow is a look brighter; together they produce a ring. Typically you see only the darkened band of sky and a second, dimmer arc, with its colors in top half of this ring because there are not enough drops near the ground reverse order. Inside the main bow are greenish and purplish arcs to fill out the bottom half. “The rainbow is just a distorted image of the known as supernumerary bows. The rainbow can vary in brightness sun,” write atmospheric scientists Raymond Lee, Jr., and Alistair Fraser along its width or length, and it can split into multiple bows near the in their definitive bookThe Rainbow Bridge. top. Viewed through polarizing sunglasses, the rainbow waxes and The angle of 138 degrees means you see the rainbow when standing wanes as you tilt your head. with your back to the sun. The lensing angle varies slightly with wave- The basic scientific explanation for rainbows dates to Persian length, separating the white sunlight into colored bands. Multiple physicist Kam ¯al al-D¯in al-F ¯aris¯i and, independently, German physicist reflections within droplets create the outer bows; wave interference

Theodoric of Freiberg in the 14th century. But scientists continued to accounts for the supernumerary arcs; flattening of the droplets causes Getty Images work on the theory into the 1970s and beyond [see “The Theory brightness variations along the arc; multiple droplet sizes produce split of the Rainbow,” by H. Moysés Nussenzveig; Scientific Am e r i c a n , bows; and light is polarized much like the glare on any watery surface. April 1977]. Many textbook explanations of rainbows are wrong, Even this physics does not touch on how our eyes and brains perceive and a thorough description is still elusive. “The rainbow has the the continuous spectrum as discrete colors. The weaving of the rainbow

undeserved reputation of having a simple explanation,” says atmo- occurs in our heads as much as it does in the sky. —George Musser PHILIPANDKAREN SMITH

f only my car could fl y! Who has not uttered this cry in traffi c? But what motivated the people who began designing fl ying cars near ithe turn of the 20th century? Most aviation pioneers of the time were thinking not in terms of fl ight alone but of “personal mobility” and getting cars to take wing, according to John Brown, editor of the Internet magazine Roadable Times. In fact, he notes, “the true brilliance” of the Wright Brothers— who demonstrated sustained, controlled powered fl ight at Kitty Hawk, N.C., in 1903—was their decision to concentrate solely on fl ying and lovE “forget about the roadability part.” Of course, over time, additional reasons for pursuing fl ying cars Large came into play. Near the end of World War I, for instance, a Chicagoan named Felix Longobardi had military fl exibility in mind. In his patent brains may application, submitted in June 1918, he detailed a contraption that was a fl ying car as well as a gunboat—“for anti-air-craft purposes”—and a have led submarine. (It saw neither light of day nor eye of fi sh.) Even before World War I ended, Glenn H. Curtiss, the legendary to the aircraft designer, submitted a patent for an “autoplane” that he intended to be a “pleasure craft.” And Moulton B. Taylor, whose Aerocar was evolution famously used by actor Robert Cummings, wrote in his 1952 patent ) application that he wanted his invention to be suitable “for air or of amour

ﬂ y i n g c a r highway travel, and inexpensive enough to appeal to a potentially large market.” To date, dozens of patents for fl ying cars have been issued, and more or most creatures, procreation is an emotionally uncomplicated than 10, including a successor to the Aerocar, are under serious develop- affair. In humans, however, it has a tricky accomplice: romantic ); GETTY IMAGES ( ment. One developer, Terrafugia in Woburn, Mass., is perfecting (and flove, capable of catapulting us to bliss or consigning us to taking $10,000 deposits for) the Transition, a light sport plane that is not utmost despair. Yet capricious though it may seem, love is likely to be meant for everyday driving. After landing at an airport, though, pilots an adaptive trait, one that arose early in the evolution of our lineage. clasped hands clasped ( should be able to fold the wings electronically and just drive the rest of Two of the hallmarks of human evolution—upright walking and the way to their destination. Test fl ights in March went well, but whether large brains—may have favored the emergence of love, according to a the company will take off as hoped remains to be seen. —Ricki Rusting theory advanced by anthropologist Helen Fisher of Rutgers University. Getty Images Bipedalism meant that mothers had to carry their babies, rather than CON VAIR CAR , MODEl 118, designed by Theodore P. Hall, did well letting them ride on their back. Their hands thus occupied, these moms in a 1947 test fl ight, but a later crash dashed needed a partner to help provision and protect them and their newborns. Ancient bipedal hominids such as Australopithecus afarensis, the MARILIFORASTIERI hopes for commercialization. species to which the 3.2-million-year-old Lucy fossil belongs, probably formed only short-term pair bonds of a few years, however—just long enough for the babies to be weaned and walking, after which females were ready to mate anew. The advent of large brains more than a million years ago extended the duration of these monogamous relationships. As brain size expanded, humans had to make an evolutionary trade-off. Our pelvis, built for bipedalism, places a constraint on the size of a baby’s head at birth. As a result, human babies are born at an earlier stage of development than are other primate infants and have an extended childhood during which they grow and learn. Human ancestors would thus have benefi ted from forming longer-term pair bonds for the purpose of rearing young. Fisher further notes that the ballooning of the hominid brain (and the novel organizational features that accompanied this growth) also provided our forerunners with an extraordinary means of wooing one another—through poetry, music, art and dance. The archaeological record indicates that by 35,000 years ago, humans were engaging in these sorts of behaviors. Which is to say, they were probably just as lovesick as we are. —Kate Wong

ony’s Walkman portable audio cassette megabytes, enough for about half an hour of player in 1979 improved on the transistor audio. A slew of similar gadgets followed, some Sradio by allowing people to take their of which replaced the flash memory with com- preferred music wherever they went (engineer pact hard drives capable of holding thousands of Nobutoshi Kihara supposedly invented the device songs. The breakthrough product was Apple’s so that Sony co-chairman Akio Morita could 2001 iPod. Technologically, it was nothing new, listen to operas during long flights). But the but the combination of its physical sleekness, digital revolution in personal audio technology its spacious five-gigabyte hard drive and its was another two decades in the making and had thumbwheel-based interface proved compelling. implications beyond both the personal and audio. Today digital players are as likely to hold photo- Portable music went digital in the 1980s with graphs, videos and games as music, and they are the rise of devices built around CDs, mini discs increasingly often bundled into mobile phones and digital audiotape. In the 1990s the Moving and other devices. Meanwhile digital downloads rose from $138 Picture Experts Group (MPEG) developed a MP3s—immaterial and easily copied—freed million in 2004 to $1 billion last year; however, standard that became the MP3, a format that music from the physical grooves in vinyl or plastic says Russ Crupnick, a senior industry analyst at highly condenses audio files by discarding imper- media. They also dealt a severe blow to the NPD Entertainment, peer-to-peer shared files ceptible sounds (although discriminating audio- recording industry, which long resisted selling outnumber legal downloads by at least 10 to one. philes tend to disagree with that description). MP3s, prompting music lovers to distribute files Looking ahead, he believes music will not be The Eiger Labs MPMan F10, which hit the on their own. Since 2000, CD sales plummeted something to possess at all: the industry’s salva- market in 1998, was the first MP3 player to store from $13 billion to $5 billion, according to the tion (if any) may come from paid access to songs music on digital flash memory—a whopping 32 Recording Industry Association of America. streaming from the Web. —Christie Nicholson

Asteroids The small fry of the solar system have troubled pasts

or many people, asteroids are big rocks that drift Some of those bodies then agglomerated into planets; menacingly through space and are great places to some, accelerated by the gravity of larger bodies, were Fhave a laser cannon dogfight. Conventional scientific flung into deep space; some fell into the sun; and a tiny few wisdom holds that they are the leftover scraps of planet did none of the above. Those survivors linger in pockets formation. Their full story, though, is rather more complex where the planets have left them alone, notably the gap and still only dimly glimpsed. What planetary scientists between the orbits of Mars and Jupiter. Gradually they, lump together as asteroids are far too diverse—from boul- too, are being picked off. Fewer than one in 1,000, and ders to floating heaps of gravel to mini planets with signs perhaps as few as one in a million, of the asteroids original- of past volcanic activity and even liquid water—to have a ly in the main belt remain. single common origin. Smaller asteroids are not relics but debris. They come in Only the largest, more than about 100 kilometers an assortment of sizes that indicate they are products of a across, date to the dawn of our solar system 4.6 billion chain reaction of collisions: asteroids hit and shatter, the )

years ago. Back then, the system was basically one big fragments hit and shatter, and so on. Some are rocky; some asteroids swarm of asteroids or, as researchers call them at this early are metal—suggesting they came from different layers . ( stage, planetesimals. How it got that way is within the original bodies. About a third of asteroids be- , inc a puzzle, but the leading idea is that long to families with similar orbits, which can be rewound primordial dust swirling around the in time to a single point in space, namely, the location of researchers nascent sun coagulated into pro- the collision that birthed them. Because families should hoto

gressively larger bodies. disperse after 10 million to 100 million years, asteroid ); P

formation by collision must be an ongoing process. iPod . ( Indeed, so is planet formation. Whenever an asteroid hits a planet, it helps to bulk it up. Asteroids are not the leftovers of planet formation so much as they are the finishing touches. —George Musser COURTESY OF APPLE, inc

Lisa Spindler Getty Images (ear); CORBIS (battery) A cell phones and laptop computers circuit allows electrons to flow but not ions. not but flow to electrons allows circuit itbecause allows ions to flowbut notwhereas the solid, electrons, external be can which electrolyte, liquid or an gelatinous. It is that the makes electrolyte work, the battery through cathode the to anode the the charges within its innards by moving positively charged ions from keep to start they before more from electrons joining. To cathode keep the juice the going, a balances on battery many so accumulate only and can repel, electrons charges like far: very you take not would your teeth. electrons will flow and carry out work out carry and and flow circuit, a will through two electrons the Connect cathode. the other, the wants to give (which aelectrons carry negative charge) electric to the same ever since. hasOne, Every the battery two electrodes. anode, 1799. of end the at battery first the built they actually work not have known how Their inventor may ions’ motion restores the imbalance of charges and allows the flow of of flow the allows and charges of to electricity continue The imbalance the electrolyte. restores the motion through ions’ flowing by so do can They cathode. the charged ions and toward are the attracted accumulating in electrons The the lithium atoms stripped into of their electrons thus become positively electrons release atoms circuit, external where they cathode. reach the more electron-thirsty lithium anode's the operation, During lithium atoms and a made cathode of substance. some lithium-based says. works,” Pancaldi how the battery moving outside. “It took a century before experts reached a consensus on battery, the positive the charges moved in opposition whatever to the But “electric fluid” electrons. nature and of the ions charge carriers, Volta atoms, probably of was not aware that existence in his the about electrodes and wet cardboard as an electrolyte. At the time, no one knew Universi the at Italy. historian in science a Bologna of ty Pancaldi, Giuliano says rays, electric organs in the that fishproduce torpedoes, electricity alsoknown as energetically struggle, which speaking, is uphill why it an ions) amounts to is storing energy in the battery. This lithium the side. (and graphite the electrons to the move makes electrodes two the between www.ScientificAmerican.com www.ScientificAmerican.com For example, a charged lithium-ion battery lithium-ion charged a example, For Simply from electrons one shifting material to another, however, Although different designs exist, different Although the basic has structure remained Volta probably went by trial and error before settling on using metal the replicate to trying was Volta battery, first his built he When applied voltage a process: the reverses battery the Recharging Italian scientist Alessandro Volta sought to tap into when he he when into tap to sought Volta Alessandro scientist Italian to It substances. migrate isdifferent between the power that battery’s power comes from the tendency of electric charge — at least until the anode runs out of lithium. B atte — has a graphite anode stuffed with with stuffed anode graphite a has —

say, lighting a bulb or brushing — the type that powers

— Davide Castelvecchi Davide ri

s - L the human head and external ears. ears. external and head human the that turn toward the sound of a are disturbance also being modeled on reproduce better to aids natural hearing aural Robots mechanics. and of automated surveillance cameras design the informing are sounds and the clues to its source. hearing, Studies of on how human pinnae filter and reflect heavily relies that barn owl, hunter instead uses its night large ruff of facial Another feathers to capture sound signals. sonar pinnae whose bats, than sense range in hearing shapes and sizes tailored to the directional frequencies of each keener a species’ own has animal sounds in the range of human speech to the inner ear. they of them. This so-called notch-filtering effectpreferentially delivers vibrations, incoming reflect in sounds a way out that some cancels delay the higher-frequency slightly the pinnae the of entering contours sounds of the As canal. frequency ear the modulate usefully also pinnae our entire The effectively. more sounds human ear have structure those to amplifies sounds by funnel onlythought about and are 10 to 15 capture pinnae, decibels, to but called evolved flaps, cartilage and skin external fancier middle-ear setup, higher-frequency sounds are also audible; To which have vibrations. mammals, a low-frequency transmit crudely lizards, birds and mammals. Reptilian eardrums can do no more than ear evolved separately and repeatedly in the ancestors of frogs, turtles, mammals of feature evolved distinguishing a from are what used to that be gill arches bones in ear fish and jawbones middle in reptiles. mitting with the in ears jaw tandem of is the sound-trans embryonic no accident: es. Because development often reprises stages of evolution, the growth shell shape so up for handy on holding eyeglass the taking recognizable migrate up the face as the jaw becomes more pronounced and start bumps destined to form an ear. By nine weeks, these “hillocks” will Ex the sensitive middle ear They guide sound to Pinnae also help to detect where a sound comes from. Perhaps no middle the outside just sits that eardrum, or membrane, tympanic The eyes and on either side of its shallow mouth slit, half a dozen small small dozen a half slit, mouth shallow its of side either on and eyes six- a else, anything week-old than human embryo has tiny paddles salamander for hands, baby dark a dots for like more ooking te rnal rnal Ears S CIENTIFIC AMERIC —

Christine Soares A N

57 - - origins Insurance Its probability-based view of misfortunes helped to shape the scientific outlook

he first “insurance policy” on record is probably the Codex Hammurabi, circa 1780 B.C., which you can still read in the Toriginal at the Louvre Museum in Paris if you are nimble with ancient Sumerian legalese. It avers that shippers whose goods were lost or stolen in transit would be compensated by the state. (How did shippers prove their claims? A sworn declaration before a god was good enough for the king of Babylon.) Another 3,500 years or so passed before a catastrophe—the Great Fire of London in 1666—begat the first instance of “modern” insurance: a formal setup whereby people paid premiums to companies to Scotch Tape bail them out in an emergency; actuaries for the companies set the premium rates based on risk of payout. Such insurance depended on Most new inventions quickly advancements in higher mathematics—namely, probability theory. That development has been insurance’s lasting and profound legacy fall into oblivion; some stick for modern life, coloring the way we think about so many things, including ourselves. n 1930 food-packing companies were enthralled with the relatively Mathematical probability theory began in the mid-16th century, new and improved film called cellophane, a transparent polymer when European scholars first applied hard analysis to gambling games. Imade from cellulose. Cellophane wrappers could help keep pack- The goal, a hallmark of the Enlightenment, was to lay reason on ran- aged food fresh yet would still allow customers a view of the contents. domness. Deadly storms, plagues and other misfortunes were under- Sealing cellophane packages satisfactorily was a problem, however, stood to be merely unfortunate but natural (and rare) events, not until the 3M Company invented and trademarked Scotch tape—a name portents—less scourges to be feared and more mysteries to be solved. that the public nonetheless widely uses for all adhesive-backed cello- Thus did probability crunching find its way into modern science. phane tapes. (The analogous product Sellotape, introduced seven years Geneticists use it to divine the likelihood that parents will have children later in Europe, has the same problems with generic use of its name.) with a particular birth defect. Particle physicists use it to allay fears that Engineers call the glue in Scotch tape a pressure-sensitive adhesive. the new supercollider will produce an Earth-swallowing black hole. We It does not stick by forming chemical bonds with the material it is organize our lives—from indulgences to duties—with the probabilistic placed on, says Alphonsus Pocius, a scientist at the 3M Corporate expiration date of our life span in mind. At every turn, we subconscious- Research Materials Laboratory in St. Paul, Minn. Instead applied pres- ly intuit that this or that outcome is likely to happen, but those intu- sure forces the glue to penetrate the tiniest microscopic irregularities on itions are pliable. It is the real-world testing of our biases—the scientific the material’s surface. Once there, it will resist coming back out, thus method—that confirms or kills them. keeping the tape stuck in place. The glue “has to be halfway between The legacy of insurance industry risk crunching is not all positive: its liquid and solid,” Pocius explains: fluid enough to spread under pres- fingerprints are all over the recent massive upheaval on Wall Street. A sure but viscous enough to resist flowing. formula published in 2000 by actuary David X. Li, who went on to head Concocting the right kind of glue is only part of the invention, research divisions at Citigroup and Barclays Capital, and however. The typical adhesive tape contains not just two materials ) widely used by economists and bankers to estimate (glue and backing, which can be cellophane or some other plastic) the risk of asset-backed securities borrowed a but four. A layer of primer helps the glue stick to the plastic, key component from life insurance. The while on the other side a “release agent” makes sure that the Hammurabi's Code Hammurabi's

formula, called a Gaussian cupola function, glue does not stick to the top. Otherwise, Scotch tape would ( was not so much an application of actuari- be impossible to unroll. al science as a misapplication of it. As it Adhesive tape recently caught the attention of physi- ollection turns out, the default risk of financial cists. Researchers showed that unrolling tape in a vacuum C instruments cannot be predicted in the chamber releases x-rays, and they used those x-rays to same way that, say, the death risk of image the bones in their fingers as a demonstration. The ranger ); G

spouses can. discovery could lead to cheap, portable (and even muscle- tape ( Oops. —Bruce Grierson powered) radiography machines. The unrolling creates electrostatic charges, and electrons jumping across the gap

HAMMURABI'S CODE, inscribed on between tape and roll produce x-rays. In the presence of GettyImages B.C. a black basalt slab about 1780 , air the electrons are much slower and produce no x-rays. unto holds a record of the first But try unrolling tape in a completely dark room, and you auntyJ

"insurance policy." will notice a faint glow. —Davide Castelvecchi J

ost medically important antibiotics come from soil bacteria. or of “quorum-sensing” bacteria that assess their own numbers. Conventional wisdom holds that dirt microbes evolved these “I’m not saying that some of these compounds couldn’t be used as Mcompounds as lethal weapons in the fierce battle waged beneath weapons in nature,” Davies says. “But that’s not what we’re seeing.” He our feet for food and territory. For more than 15 years microbiologist Julian notes that a gram of soil contains more than 1,000 different types of bacte- Davies of the University of British Columbia has been arguing otherwise. ria. “They’re all thriving there together and clearly not killing one another.” “They’re talking, not fighting,” Davies says. Davies proposes that many antibiotics may help coordinate bacterial activi- His respected if not wholly accepted theory is that bacteria use most of ties such as swarming, biofilm formation and diverse interactions with their the small molecules we call antibiotics for communication. As evidence, multicellular hosts. Davies points out that in nature, soil bacteria secrete antibiotics at trace Davies’s theory implies both good news and bad for the world of medi- levels that do not come close to killing their microbial neighbors. “Only cine. Bacterial communities (and not just those in dirt) might be treasure when we use them at unnaturally high concentrations do we find that these troves of chemicals with microbe-killing drug potential. Davies and his chemicals inhibit bacteria,” he explains. colleagues have already found candidate molecules among gut bacteria Moreover, in Davies’s Vancouver laboratory, his staff has been eaves- such as Escherichia coli. But for every new antibiotic, there may also already dropping on the flurry of gene activity in bacteria exposed to low-dose be plenty of corresponding resistance genes. After all, the same bacteria antibiotics. The researchers equip their bacteria with glow-in-the-dark that regularly produce and respond to antibiotics need mechanisms for lux genes that provide a fluorescent signal when other linked genes protecting themselves from potentially toxic effects. And in the gene- are active; then they watch those genetic “switchboards” light up in swapping world of bacteria, it doesn’t take long for such DNA instructions a chorus of responses to antibiotic exposure. The call-and-response to jump from one species to many once a new antibiotic comes into wide- activity resembles that of cells responding to hormones, Davies observes, spread medical use. —Jessica Snyder Sachs

Artificial Heart Did the wrong man get credit for the world’s first permanent pump?

n January 1982 surgeons at the University of Utah implanted the first permanent artificial Iheart into Barney Clark, a 61-year-old dentist from Seattle who was hours from death as he went into the operating room. He would live another 112 days. The work was a triumph for Willem Kolff, founder of the university’s Division of Artificial Organs and head of the team that developed Clark’s new heart. Yet in the weeks that followed the surgery, Kolff’s name began to be left out of the frantic media coverage. Nearly three decades later he has been all but forgotten. Perhaps he should have named the heart after himself. investigators in his lab to keep them motivated and prevent them from Kolff was already one of the world’s foremost inventors of artificial moving elsewhere. Jarvik was project manager for the iteration that organs when he moved in 1967 from the Cleveland Clinic to Utah. Ten came to be named Jarvik-7. That device was approved for use by the years earlier he had invented the first working artificial kidney; that Food and Drug Administration in 1981. same year he began work on a heart. At Utah, Kolff led a team of more Jarvik was 35 years old when Clark received the heart that bore his than 200 doctors and scientists who were pushing to advance the field name. He appeared at the press conference that announced the implant of artificial organs. In 1971 he hired Robert Jarvik, a budding researcher in scrubs, although he did not take part in the surgery. Jarvik continued Photo Researchers, Inc. in biomechanics who seemed to have a knack for engineering. Jarvik to attend press conferences at the center, while Kolff kept a low profile. began medical school the next year and continued to work on improv- Perhaps it is not surprising that the world came to associate a seminal organ

M ing the heart through his graduation in 1976. piece of engineering—the work of hundreds, over a course of years—

H ank Kolff had a tradition of naming new versions of the heart after young with one man. After all, it had his name on it. —Michael Moyer

n the final year of World War I, when the German military pointed its largest artillery at Paris from a distance of 75 miles, the troops adjust- Ied the trajectory for many factors that could be ignored with less powerful guns. In particular, a subtle influence from the rotation of the earth—the Coriolis effect or force—would have shifted all their shots by about half a mile. Decades earlier a Parisian scientist by the name of Gaspard-Gustave de Coriolis had written down the equations describing that effect as a part of his 1835 paper analyzing machines with rotating parts, such as waterwheels. The Coriolis effect can arise in any situation involving B all Bearings rotation. If you stand anywhere on a counterclockwise-turning carousel, for instance, and throw a ball in any direction, you will see the ball’s Cheap steel was key to trajectory curve to its right. Someone standing next to the carousel will see the ball move in a straight line, but in your rotating frame of refer- allowing the routine design ence the ball's direction of motion swings around clockwise. A new force appears to act on the ball. On the spinning earth, we see a similar of parts that rolled against (but much weaker) force acting on moving objects. As well as deflecting the paths of long-range artillery shells and one another ballistic missiles, the Coriolis effect is what causes cyclones (which includes hurricanes and typhoons) to spin clockwise south of the equa- f the utility of an invention were somehow derived from the genius tor and counterclockwise north of it. Indeed, the Coriolis effect is the of its inventor, it would be pardonable that so many sources trace reason that winds in general tend to flowaround regions of high and Ithe idea for the ball bearing to a 1497 drawing by Leonardo da Vinci. low pressure, running parallel to the lines of constant pressure on a But good ideas, like useful evolutionary traits, tend to emerge more weather map (“isobars”), instead of flowing directly from high to low than once, in diverse times and places, and the idea of arranging for pressure at right angles to the isobars. In the Northern Hemisphere, air parts to roll against one another instead of sliding or slipping is very flowing radially inward across the isobars toward the low pressure old indeed. The Egyptians already had the basic idea when they moved would be deflected to the right. The motion reaches a steady state with great blocks of stone on cylindrical rollers. Similar ideas occurred to the wind encircling the low-pressure area—the pressure gradient the builders of Stonehenge as early as 1800 B.C. and to the craftsmen pushing inward and the Coriolis force outward. who constructed the cylindrical-shaped bearings on the wheel hubs A popular factoid claims that water running down a drain turns in one of wagons around 100 B.C. (On these wagons the axle turned with direction in the Southern Hemisphere and the opposite way in the North- the wheels, so the bearings enabled the axle to roll against the ern Hemisphere. That idea is a myth: although the Coriolis force is strong wagon chassis.) enough to direct the winds of hurricanes when acting over hundreds of The first design for a ball bearing that would support the axle of a miles for days, it is far too weak to stir a small bowl of water in the scant carriage did not appear until 1794, in a patent filed by a Welsh ironmas- seconds the water takes to run down the drain. —Graham P. Collins ter named Philip Vaughan. Ball bearings between the wheel and the axle enabled the axle to remain fixed to the carriage chassis. But cast iron ball bearings were brittle and tended to crack under stress. It took

the invention of the Bessemer process for making inexpensive steel, ) plus the invention of the bicycle, to fix the ball bearing permanently in

the minds of engineers everywhere. Jules-Pierre Suriray, a Parisian bearing ball bicycle mechanic, patented his steel ball-bearing design in 1869, and in ( that same year a bicycle outfitted with Suriray’s ball bearings won an Corbis international cycling race. chroll The demand for ball bearings—on automobiles, tanks or guidance systems—has pushed manufacturers ever closer to the ideal of shaping olframS a perfect sphere. No turning wheel will survive for long on its axle ); W ); without ball bearings machined to a tolerance of less than a thou- missile sandth, or even a 10-thousandth, of an inch. ( Corbis

Many sources claim that the most perfect spheres occur in the bearings of computer hard drives, but in fact that honor goes to the

ping pong–size spheres of fused quartz that serve as gyroscopic bear- unning D Titan II Missile fired across 7,000 miles typically would be ings for the satellite Gravity Probe B. Its gyroscopes are 30 million times ichael

deflected hundreds of miles by the Coriolis force. more accurate than any other gyroscope ever built. —Peter Brown M

aleontologists used to wonder whether the first teeth were on the differs from the instructions that build a jaw, even though both types of inside or the outside of prehistoric bodies. Sharks are covered in structure grow in tandem. The marriage of tooth and jaw, however, likely Pthousands of tiny denticles–toothlike nubs of dentine and collagen gave rise to specialized tooth shapes. By the 10th day of a human embryo’s that make sharkskin coarse to the touch. If the denticles of some very early development, molecular signaling that initiates tooth formation is taking vertebrate had migrated into the jaw, grown larger and gained new functions, place between two basic embryonic tissue layers. At the same time, signals the speculation went, they could have given rise to modern choppers. But over from the growing jaw imprint a shape onto the primordial tooth that cannot the past decade fossil and genetic evidence has confirmed that teeth are much be changed. Even when the bud of a future molar, for instance, is trans- older than even the ancient shark lineage—indeed, older than the jaw or the planted into a different area of the jaw, the final tooth will become whatev- denticle. And they originated inside the body, though not in the mouth. er its original location fated it to be. The first sets of teeth belonged to eel-like swimmers that lived some 525 Unfortunately, dental researchers are finding it difficult to recapitulate million years ago and ranged from four to 40 centimeters long. Collectively half a billion years of evolution in the laboratory. Because burgeoning teeth they are known as conodonts for the ring of long, conical teeth in their depend on information from the budding embryonic jaw, work toward pharynx. Some fish species still have a set of vestigial teeth in their throat, generating replacement teeth from dental stem cells focuses on growing but pharyngeal teeth for the most part are believed to have migrated for- them in the desired location in the recipient’s mouth–but scientists are not ward into the mouth, perhaps as the jaw was evolving. yet sure the adult jaw can provide the necessary signals to shape made-to- Supporting that idea, the programmed gene activity that builds teeth order teeth. —Christine Soares

Egg The answer to the age-old riddle is biologically obvious

n March 2006, on the occasion of the release of a group of animals to cease Chicken Little on DVD, Disney convened a panel interbreeding with another Ito put an end to the long-standing riddle: Which group; only then can we say that came first, the chicken or the egg? The verdict was speciation has occurred. Viewed in unanimous. “The first chicken must have differed this way, it does not make sense to talk from its parents by some genetic change [that] about the first chicken or the first egg. There caused this bird to be the first ever to fulfill our was only the first group of chickens—some of criteria for truly being a chicken,” said John Brook- whom, presumably, were in egg form. field, an evolutionary biologist at the University of And if one relaxes the species qualification, Nottingham in England. “Thus the living organism then the race is not even close. Invertebrates as inside the eggshell would have had the same DNA simple as sponges rely on some form of egg for as the chicken that it would develop into, and thus reproduction, which means that eggs probably would itself be a member of the species of chick- predate the Cambrian explosion in biodiver- en.” What we recognize as the DNA of a chicken sity of 530 million years ago. Fish and exists first inside an egg. Egg came first. amphibians lay gelatinous eggs; ancestors Yet despite the unified front of the three-person of reptiles and birds laid the first shelled panel—David Papineau, a philosopher of science, eggs 340 million years ago, and that and Charles Bourns, a chicken farmer, agreed in spirit innovation, which allowed their eggs with Brookfield’s analysis—the question is at best to survive and mature on dry land, incomplete, at worst misleading. If we take “chick- enabled the rise of land verte- en” to mean a member of Gallus gallus domesticus brates long before the first (a subspecies of junglefowl that evolved in Southeast rooster crowed. Asia and has been domesticated for perhaps 10,000 —Michael Moyer years), we could ask at what point the first member

Getty Images of this species appeared (and whether it was in bird art or egg form). Yet speciation is not a process that kiH K i happens in an instant or in an individual. It takes generations on generations of gradual change for andV GK

ulticellularity has its advantages, but they come at a price. control. He attributed the dysfunction to an excess of black bile. The division of labor in a complex organism means that Modern scientists see a breakdown of the cellular regulatory system in Mevery cell must perform its job and only its job, so an elabo- the hallmarks of cancer: runaway growth, invasion of neighboring rate regulatory system evolved to keep cells in line. Nearly every one tissue and metastasis to far-off parts of the body. of the trillion or so cells in the human body, for instance, contains The proteins and nucleic acids that control gene activity are them- a full copy of the genome – the complete instruction set for building selves encoded by genes, so cancers begin with mutations that either and maintaining a human being. Tight controls on which genes disable key genes or, conversely, cause them to be overactive. Those are activated, and when, inside any given cell determine that cell’s changes initiate a cascade of imbalances that knock out downstream behavior and identity. A healthy skin cell executes only the genetic regulatory processes, and soon the cell is careening toward malignan- commands needed to fulfill its role in the skin. It respects neighbor- cy. So far efforts to identify the exact combination of mutations neces- ing cells’ boundaries and cues, and when the regulatory system sary to ignite a particular type of cancer—in the brain, the breast or permits, it divides to generate just enough new cells to repair a wound, elsewhere—have not yielded clear patterns. Once regulatory networks never more. are destabilized, they can break down in ways as complex and diverse Greek physician Hippocrates first used the termkarkinos, or “crab,” as the molecular pathways they regulate, making the precise origin of in the fourth century B.C. to describe malignant tumors because their each instance of cancer unique. For all their internal chaos, though, tendril-like projections into surrounding tissue reminded him of the cancer cells share some characteristics with stem cells—those primal arms of the crustacean. In Latin, the word for crab was cancer, and by body-building cells that are exempt from many constraints on normal the second century B.C. the great Roman physician Galen knew those cells. One important difference is that in stem cells, the full potential of spiny arms were just one sign that normal body tissues had gone out of the genome is controlled; in cancer, it is unleashed. —Christine Soares

The Stirrup Invention of the stirrup may rival that of the longbow and gunpowder

slight alteration to the custom of riding arm, use the tremendous force of the charging a horse may have dramatically horse to strike a stunned enemy. The horse's Achanged the way wars were fought. sheer mass and quickness became an implement Humans rode bareback or mounted horses with of the cavalry's weaponry—and a powerful a simple blanket after they first domesticated intimidation factor. the animals, thousands of years after the dawn The fierce Avar tribe may have brought of agriculture. The leather saddle first straddled stirrups to the West when it arrived in Byzantium a horse’s back in China perhaps as far back as in the sixth century A.D. The Byzantine Empire the third century B.C. But the saddle was only soon adopted the stirrup—and later the Franks one step toward transforming the use of cavalry embraced it as well. The societal impact of this as a means of waging war. Climbing onto a horse saddle accoutrement has intrigued historians for while bearing weapons had long presented its decades. Some scholars suggested that feudal- own precarious hazards. Cambyses II, a Persian ism emerged in Europe because mounted war- king in the sixth century B.C., died after stabbing fare, facilitated by the stirrup, became vastly himself as he vaulted onto a horse. more effective for the cavalry of the Franks. An By the fourth century A.D., the Chinese had aristocratic class emerged that received land for begun to fashion foot supports from cast iron or its service in the cavalry. bronze. What made the stirrup (derived from the Others, on the opposite side of what is Old English word for a climbing rope) such an known as the Great Stirrup Controversy, argue important innovation was that it allowed the that this interpretation of events is baseless. rider immensely greater control in horseman- Whether the stirrups were the single enabling ship: rider and animal became almost extensions technology that brought about the rise of of each other. It was possible to shoot arrows feudalism remains in doubt. Unquestionably, accurately while the horse dashed ahead at full though, this small extension from a saddle mages gallop. A cavalryman could brace himself in the was an innovation that transformed the craft of I

saddle and, with a lance positioned under his war forever. —Gary Stix G etty

n a world without cooking, we would have to spend half our days chewing raw food, much as the chimpanzee does. Cooking not only Imakes food more delicious, it also softens food and breaks starches and proteins into more digestible molecules, allowing us to enjoy our meals more readily and to draw more nutrition from them. According to Harvard University biological anthropologist Richard Wrangham, cooking’s biggest payoff is that it leaves us with more energy and time to devote to other things—such as fueling bigger brains, forming social blotter art decorates LSD-infused absorbent paper with relationships and creating divisions of labor. Ultimately, Wrangham color palettes reminiscent of the psychedelic era of the 1960s. believes, cooking made us human. Archaeological evidence is mixed as to when our ancestors started building controlled fires—a prerequisite for cooking—but Wrangham argues that the biological evidence is indisputable: we must have first LSD enjoyed the smell of a good roast 1.9 billion years ago. That is when a species of early human called Homo erectus appeared—and those An inquisitive Swiss hominids had 50 percent larger skulls and smaller pelvises and rib cages than their ancestors, suggesting bigger brains and smaller abdomens. chemist sent himself They also had much smaller teeth. It makes sense that cooking “should have left a huge signal in the fossil record,” Wrangham says, and, quite on the first acid trip simply, “there’s no other time that fits.” Never before and never again during the course of human evolution did our teeth, skull and pelvis he medical sciences can invoke a long and storied tradition of change size so drastically. If cooking had arisen at a different point, he self-experimentation. Typhoid vaccine, cardiac catheterization, says, we would be left with a big mystery: “How come cooking was Teven electrodes implanted in the nervous system came about adopted and didn’t change us?” because scientists recruited themselves as their own guinea pigs. Wrangham also has a theory as to how controlled fires, and thus One of the most memorable instances happened on April 16, 1943, cooking, came about. He speculates that H. erectus’s closest ancestors, when Swiss chemist Albert Hofmann inadvertently inhaled or ingested the australopithecines, ate raw meat but hammered it to make it flatter a compound derived from a crop fungus that went by the chemical and easier to chew, rather like steak carpaccio. “I’ve tried hammering name of lysergic acid diethylamide, or LSD-25. He subsequently entered meat with rocks, and what happens? You get sparks,” he says. “Time into “a not unpleasant intoxicated-like condition, characterized by an and time again this happens, and eventually you figure out how to extremely stimulated imagination,” he recalled in his 1979 autobiogra- control the fire.” —Melinda Wenner phy, LSD, My Problem Child. “In a dreamlike state, with eyes closed ...” he continued, “I perceived an uninterrupted stream of fantastic pictures extraordinary shapes with intense, kaleidoscopic play of colors.” Ever the intrepid researcher, Hofmann decided to probe further the psychotropic properties of the substance, which Sandoz Laboratories ) had previously developed and then abandoned as a possible stimulant relief ( for breathing and circulation. A few days after his first trip, he carefully apportioned a 0.25-milligram dose; within a short time the Sandoz mages I laboratory where he worked again became distorted and strange. The etty

); G words “desire to laugh” were the last ones scrawled in his research LSD

( journal that day. His inebriated state prompted him to leave work early. The bicycle ride home—in which he could not tell that he was moving— has given April 19 the designation of “bicycle day” among LSD aficio- nados everywhere. Hofmann went on to use LSD hundreds of times more—and his Photo Researchers, Inc. creation became a ticket into the altered mental states embraced by the counterculture. Though subsequently banned, the drug continues to

tammers attract intense interest by investigators who are examining therapeutic uses, including the possibility that it may help the terminally ill reconcile bread making relief image decorates an Egyptian tomb inclairS

S themselves to their mortality. —Gary Stix dating back more than 4,000 years.

undials and water clocks are as old as civilization. Mechanical what we perceive as “change” is not variation in time but a pattern among clocks—and, with them, the word “clock”—go back to 13th-centu- the universe’s components—the fact, for example, that if Earth is at a Sry Europe. But these contraptions do nothing that nature did not certain position in its orbit, the other planets are at specific positions in already do. The spinning Earth is a clock. A dividing cell is a clock. Radioac- theirs. Physicist Julian Barbour developed this relational view of time in the tive isotopes are clocks. So the origin of clocks is a question not for history winning entry for the Foundational Questions Institute essay contest last but for physics, and there the trouble begins. year. He argued that because of the cosmic patterns, each piece of the You might innocently think of clocks as things that tell time, but accord- universe is a microcosm of the whole. We can use Earth’s orbit as a refer- ing to both of the pillars of modern physics, time is not something you can ence for reconstructing the positions of the other planets. In other words, measure. Quantum theory describes how the world changes in time. We Earth’s orbit serves as a clock. It does not tell time but rather the positions observe those changes and infer the passage of time, but time itself is of the other planets. intangible. Einstein’s theory of general relativity goes further and says that By Barbour’s reasoning, all clocks are approximate; no single piece of a time has no objective meaning. The world does not, in fact, change in time; system can fully capture the whole. Any clock eventually skips a beat, runs it is a gigantic stopped clock. This freaky revelation is known as the prob- backward or seizes up. The only true clock is the universe itself. In a sense, lem of frozen time or simply the problem of time. then, clocks have no origin. They have been here all along. They are what If clocks do not tell time, then what do they tell? A leading idea is that make the concept of “origin” possible to begin with. —George Musser

Legs, Feet and Toes The essential parts for walking on land evolved in water

he evolution of terrestrial creatures from aquatic fish with fins tetrapod ancestors in two key ways. First, they could have allowed may have begun with the need for a breath of fresh air. Animals the creatures, which lived in the plant-choked shallows, to perform Twith limbs, feet and toes—a group known as the tetrapods a push-up that raised their heads out of the oxygen-poor water (literally, “four-footed”)—arose between 380 million and 375 million for a breather. (Changes in other parts of the skeleton, such as the years ago. Scientists long believed that limbs evolved as an adaptation skull and neck, also facilitated air breathing.) The protolimbs could have to life on terra firma. But recent discoveries have revealed that some also helped these animals to propel themselves along the bottom and of the key changes involved in the fin-to-limb transition occurred to steady themselves against the current while waiting to ambush prey. while the ancestors of tetrapods were still living Researchers once thought that the bones making up feet and toes in the water. were an evolutionary innovation unique to the tetrapods. But over the Tetrapod evolution experts such past few years analyses of tetrapod forerunners, such as the Tiktaalik as Jennifer Clack of the University fossil unveiled in 2006, have revealed that these bones derive directly of Cambridge hypothesize from bones in the fish fin. Curiously, the earliest tetrapods and that these early modifica- tetrapodlike fish had feet with between six and eight digits, rather tions to the bones and than the five of most modern tetrapods. Why tetrapods ultimately joint surfaces of the evolved a five-digit foot is uncertain, but this arrangement may pectoral fins might have provided the ankle joint with the stability and flexibility needed

have benefited for walking. —Kate Wong martín raúl

or a sex toy, the vibrator’s roots seem amazingly antiseptic and clinical. Prescribed as a cure for the curious disease hysteria, the Fdevice for decades found clinical application as a supposed medical therapy. PaPer Money Derived from the Greek word for “uterus,” hysteria occurred in women with pent-up sexual energy—or so healers and early physicians A substitute for coins believed. Nuns, widows and spinsters were particularly susceptible, but by the Victorian era many married women had fallen prey as well. In the turned into a passport late 19th century a pair of prominent physicians estimated that three quarters of American women were at risk. for globalization The prescription of clitoral orgasm as a treatment for hysteria dates to medical texts from the fi rst centuryA.D. Hysterical women typically turned to doctors, who cured them with their hands by inducing a lame it on paper currency. The development of banknotes in “paroxysm”—a term that hides what we now know as a sexual climax. China more than a millennium ago accelerated wealth accumu- But manual stimulation was time-consuming and (for the doctors at Blation, defi cit spending and credit extension—paving the way least) tedious. In The Technology of Orgasm: “Hysteria,” the Vibrator for our present-day fi nancial crisis. and Women’s Sexual Satisfaction, science historian Rachel P. Maines When Chinese merchants started using paper money in the Tang reports that physicians often passed the job off to midwives. Dynasty (which spanned A.D. 618 to 907), they could have hardly The invention of electricity made the task easier. Joseph Mortimer foreseen such diffi culties. At the time, the introduction of notes that Granville patented an electromechanical vibrator in the early 1880s to could be redeemed for coins at the end of a long journey was a boon. relieve muscle aches, and doctors soon realized it might be used on Paper cut down on traders’ loads, enabling them to transport large other parts of the body. That innovation shortened treatment time for sums of money over sizable distances. hysteria, fattening doctors’ wallets. The practice caught on nationwide in the 10th century, when a Patients were happy, too. The number of health spas offering copper shortage prompted the emperor of the Song Dynasty to issue vibration therapy multiplied, and the service was so popular vibrator the world’s fi rst circulating notes. A string of earlier Chinese inven- manufacturers warned doctors not to overdo it with the modern tions—including paper, ink and block printing—made it all possible. appliance: if they met relentless patient demand, even mechanical When Marco Polo visited the Mongol Empire in the 1200s, he was vibration could be tiring. By the turn of the century needlework cata- impressed by Kublai Khan’s sophisticated mints, connecting them logues advertised models for women who to an apparently booming economy. (The explorer did not wanted to try the treatment at home, making pick up on signs of the infl ation brought on by the rapid the vibrator the fi fth electric appliance to printing of notes.) Later, faster circulation of currency arrive in the home—after the sewing ma- allowed European nations to siphon resources out of chine, the fan, the teakettle and the toaster. ) Asia and Africa, fundamentally altering the global balance The vibrator’s legitimacy as a medical of power. device declined after the 1920s, when Today paper money means that wealth fl ows back to the Sigmund Freud correctly identifi ed advertisement developing world as well. Financial convertibility makes it paroxysm as sexual. In 1952 the American possible for China to buy up U.S. bonds, fi nancing debts that Psychiatric Association dropped hysteria may never be paid back. But it also escalates the pace of from its list of recognized conditions. wealth accumulation. Paper currency—and its modern heir, When the vibrator was again popularized electronic trading—lay behind the recent commodities and years later, women no longer needed the housing bubbles, contributing to last year’s fi nancial crash. pretense of illness to justify a purchase. In today’s recession, things have come full circle. Amid —Mara Hvistendahl ); coUrtesy of Bakken mUseUm ( concerns about fi nancial stability, some investors are holding money on to precious metals. A backlash against more abstract forms SEX TOYS started off as medical of currency means a return to our economic roots: centuries devices for treating hysteria in after our conversion to paper, the price of gold has soared. women, becoming a substitute for

getty Images ( —Mara Hvistendahl manual stimulation by physicians.

www.ScientificAmerican.com Scientific AmericAn 65 © 2009 SCIENTIFIC AMERICAN, INC. © 2009 SCIENTIFIC AMERICAN, INC. origins Buckyballs and Nanotubes A once overlooked form of carbon may represent the future of technology

ullerenes, a form of solid carbon distinct from diamond and Buckminster Fuller’s similar geodesic domes. Their discovery sparked graphite, owe their discovery to a supersonic jet—but not of the research that led to elongated versions called carbon nanotubes, which Fairplane variety. At Rice University in 1985 the late Richard E. Sumio Ijima of NEC described in a seminal 1991 paper. Smalley, Robert F. Curl and Harold W. Kroto (visiting from the University Both “buckyballs” and nanotubes could have been found earlier. In of Sussex in England), along with graduate students James R. Heath 1970 Eiji Osawa of Toyohashi University of Technology in Japan postu- and Sean C. O’Brien, were studying carbon with a powerful tool that lated that 60 carbon atoms could adopt a ball shape, but he did not Smalley had helped pioneer: supersonic jet laser spectroscopy. In this actually make any. In 1952 two Russian researchers, L. V. Radushkevich analytical system, a laser vaporizes bits of a sample; the resulting and V. M. Lukyanovich, described producing nanoscale, tubular carbon gas, which consists of clusters of atoms in various sizes, is then cooled filaments; published in Russian during the cold war, their paper received with helium and piped into an evacuated chamber as a jet. The clusters little attention in the West. expand supersonically, which cools and stabilizes As it turned out, buckminsterfullerene is not hard to make. It forms them for study. naturally in many combustion processes involving carbon (even candle In their experiments with graphite, the Rice burning), and traces can be found in soot. Since the Rice discovery, team recorded an abundance of carbon researchers have devised simpler ways to create buckyballs and nano- clusters in which each contained the tubes, such as by triggering an electrical arc between two graphite equivalent of 60 atoms. It puzzled them electrodes or passing a hydrocarbon gas over a metal catalyst. Carbon because they had no idea how 60 atoms nanotubes have drawn much scrutiny; among their many intriguing could have arranged themselves so properties, they have the greatest tensile strength of any material stably. They pondered the conundrum known, able to resist 100 times more strain than typical structural steel. during two weeks of discussion, During an interview with Scientific Am e r i c a n in 1993, Smalley, who frequently over Mexican food, before died in 2005 from leukemia, remarked that he was not especially hitting on the solution: one carbon interested in profiting from fullerenes. “What I want most,” he said, “is atom must lie at each vertex of 12 to see that x number of years down the road, some of these babies are pentagons and 20 hexagons arranged like off doing good things.” Considering that nanotubes in particular are the panels of a soccer ball. They named the driving advances in electronics, energy, medicine and materials, his

molecule “buckminsterfullerene,” in tribute to wish will very likely come true. —Philip Yam retseck george

Economic Thinking Even apparently irrational human choices can make sense in terms of our inner logic

uch economic thinking rests on the assumption that individuals playing than to the outcome of potentially losing. A risk-oriented person, know what they want and that they make rational decisions on the other hand, will go for the thrill. Mto achieve it. Such behavior requires that they be able to rank Cramer’s idea was later formalized by Bernoulli’s statistician cousin the possible outcomes of their actions, also known as putting a value Daniel into the concept of expected utility, which is an implicit value given on things. to the possible outcomes of a decision, as revealed by comparing them with The value of a decision’s outcome is often not the same as its nominal the outcomes of a bet. Risk-averse and risk-oriented persons are not irratio- dollar value. Say you are offered a fair bet: you have the same chance of nal; rather they make rational decisions based on their own expected utility. doubling your $1 wager as you have of losing it. Purely rational individuals Economists generally assume that most people are rational most of the would be indifferent to the choice between playing or not playing: if they time, meaning that they know which decisions will maximize the expected play such a bet every day, on average they will be no better or no worse off. utility of their choices. (Of course, doing so requires knowing how to evalu- But as Captain Kirk might tell Mr. Spock, reality often trumps logic. Or as ate risk wisely, which people do not always do well. AIG, anyone?) Swiss mathematician Gabriel Cramer wrote in a 1728 letter to his colleague Some experiments, however, have shown that people are occasionally Nicolas Bernoulli, “The mathematicians estimate money in proportion to its unable to rank outcomes in a consistent way. In 1953 American mathemati- quantity, and men of good sense in proportion to the usage that they may cian Kenneth May conducted an experiment in which college students were make of it.” Indeed, many people are “risk-averse”: they will forfeit their asked to evaluate three hypothetical marriage candidates, each of whom chance of winning $1 to be guaranteed of keeping the $1 they have, espe- excelled in a different quality. The students picked intelligence over looks, cially if it is their only one. They assign more value to the outcome of not looks over wealth and wealth over intelligence. —Davide Castelvecchi

lthough carbon has recently acquired a bad rap because of its each. That isotope of beryllium, however, is unstable and tends to decay very association with greenhouse gases, it has also long been synony- quickly. So there would seem to be no way to form carbon or heavier elements. Amous with biology. After all, “carbon-based life” is often taken to But later in a star’s life, the core’s temperature rises above 100 million mean “life as we know it,” and “organic molecule” means “carbon-based kelvins. Only then is beryllium produced fast enough for there to be a signifi- molecule” even if no organism is involved. cant amount around at any time—and some chance that other helium nuclei But the sixth element of the periodic table—and the fourth most abun- will bump into those beryllium nuclei and produce carbon. More reactions may dant in the universe—has not been around since the beginning of time. The then occur, producing many other elements of the periodic table, up to iron. big bang created only hydrogen, helium and traces of lithium. All other Once a star’s core runs out of nuclei to fuse, the outward pressure exerted elements, including carbon, were forged later, mostly by nuclear fusion inside by the nuclear fusion reaction subsides, and it collapses under its own weight. stars and supernovae explosions. If a star is large enough, it will produce one of the universe’s most spectacular At the humongous temperatures and pressures in a star’s core, atomic flares: a supernova explosion. Such cataclysms are good, because supernovae nuclei collide and fuse together into heavier ones. In a young star, it is mostly are what disperse carbon and the other elements (some of them forged in the hydrogen fusing into helium. The merger of two helium nuclei, each carrying explosions themselves) around the galaxy, where they will form new stars but two protons and two neutrons, forms a beryllium nucleus that carries four of also planets, life ... and greenhouse gases. —Davide Castelvecchi

THE PLACENTA An eggshell membrane evolved into the organ that lets fetuses grow in the womb

ore than 120 million years mals (the exceptions, platypuses and man placentas rely on the same set of ago, while giant dinosaurs echidnas, still lay eggs to this day). ancient cell-growth genes. But later in Mcrashed through the forests What makes mammals’ live birth a pregnancy, even though the placenta in fearsome combat, a quieter drama possible is the unique organ called the does not obviously change in appear- unfolded in the Cretaceous under- placenta, which envelops the growing ance, it invokes genes that are much brush: some lineage of hairy, diminu- embryo and mediates the flow of nu- newer and more species-specific. Thus, tive creatures stopped laying eggs trients and gases between it and the placentas are fine-tuned for the needs and gave birth to live young. They mother via the umbilical cord. of mammals with different reproduc- were the progenitors of nearly all The placenta seems to have tive strategies: witness mice, which modern mam- evolved from the chorion, a thin mem- gestate for three weeks with a dozen brane that lines the inside of eggshells or more pups, versus humans, who de- and helps embryonic reptiles and birds liver one baby after nine months. draw oxygen. Kangaroos and other To last more than a week or two, the marsupials have and need only a rudi- placenta, which is primarily an organ mentary placenta: after a brief gesta- of the fetus, must prevent the moth- tion, their bean-size babies finish their er’s immune system from rejecting it. development while suckling in the To do so, the placenta may deploy a mother’s pouch. Humans and most mercenary army of endogenous retro- other mammals, however, require a viruses—viral genes embedded in the placenta that can draw nutrients ap- mammal’s DNA. Scientists have ob- propriately from the mother’s blood served such viruses budding from the throughout an extended pregnancy. placenta’s cell membranes. Viruses Recent studies have shown that the may play crucial roles in pacifying the sophistication of the placenta stems in mother’s immune system into accept- part from how different genes within it ing the placenta, just as they do in are activated over time. Early in embry- helping some tumors survive. onic development, both mouse and hu- —Davide Castelvecchi etty Images G etty

www.ScientificAmerican.com SCIENTIFIC AMERICAN 67 © 2009 SCIENTIFIC AMERICAN, INC. © 2009 SCIENTIFIC AMERICAN, INC. Graphical Perspective “Realistic” imagery depends on relatively recent cultural assumptions and technical skills

he Pioneer 10 and 11 deep-space probes carry a plaque for the early 15th-century Florence, architect Filippo Brunelleschi performed a benefit of any aliens they might run into. On it is a line drawing of a public demonstration with mirrors (then a new technology) to show how Tman and a woman. Will it make any sense to its intended audience? faithfully his paintings depicted building facades. He inspired painters such Even if extraterrestrials notice the markings and recognize them as a pic- as Donatello, Masaccio and Domenico di Bartolo (painting above); Leon ture, will they apprehend the 3-D figures? Battista Alberti worked out the math. Their rigorous geometric construc- Many of the artistic conventions we take for granted had to be invented, tions ensured that natural depth cues such as size, vertical position and tile and they reflect a specific cultural (let alone planetary) context. The per- patterns were mutually consistent for maximum verisimilitude. spective view used on the Pioneer plaque is one example. It produces the Learning to view a perspective drawing requires accepting and overlook- illusion of depth by showing distant objects smaller than nearby ones and by ing its limitations, such as its assumption of a single viewpoint. In computer ensuring that parallel lines converge on a vanishing point. Many software graphics, perspective is well suited to first-person shooter games, but The Art Archive packages now automate these techniques and enable artists to create games such as SimCity that show a bird’s-eye view use a different tech- i rt O photorealistic images with relative ease. nique, axonometric projection, elements of which go back to Chinese i agl

Yet realism has not always been an ambition of artists. Although ele- painters in the second century B.C. Not only should we wonder whether D ments of perspective go at least as far back as Greek painter Agatharchus in aliens will be able to decipher our drawings, we should also ask whether we lfredo the fifth centuryB.C. , it became popular only with the Italian Renaissance. In would recognize alien artwork if we saw it. —George Musser A

eople have fastened sheets of paper together more or less permanently ever since the Chinese Pinvented the stuff in the first or second centuryA.D. Yet according to the Early Office Museum, the Anthrax first bent wire paper clip wasn’t patented until 1867, by one Samuel B. Fay. The iconic Solving the riddle shape of the Gem paper clip (the namesake of Gem Office Products Company) that of its lethal contagion we know today did not appear until around 1892, and it was never patented. modernized the Henry Petroski, the technology historian, wrote that its development had to await the avail- understanding of disease ability of the right wire as well as machinery that could bend wire quickly enough for a box of clips to be sold for pennies. mong diseases of man and beast, anthrax stands as one of the Both the paper clip and the machine that makes it trace oldest known and certainly one of the most storied. (It is their origins to pin making. Office workers in the early Athought to be what Homer meant by the “burning plague” in 19th century stuck their papers together—literally—with pins; a pin the Iliad.) Once a common killer of grazing animals, it was also a lethal design known as the T-pin is still advertised in office products occupational hazard for humans who worked with infected hides and catalogues today. Victorian-era pin-making machinery had already livestock. Yet the cause of anthrax remained a menacing enigma until solved the problem of cheaply mass-converting wire to pins; adapting well into the 19th century, when an unassuming German country the machine’s talents to shaping wire was a relatively minor adjust- doctor entered the picture to help name it and tame it. ment that made it possible for hosts of creative wire benders to dream In the 1870s Robert Koch set out to confirm that firecracker-shaped of cashing in big. bacterial cells in the syrupy blood of anthrax-felled livestock (first Today paper clips made out of molded plastic, wire clips coated with isolated by French scientists a decade earlier) were what was killing colored plastic, and even semicircular sheets of aluminum that fold the the herds and flocks. Despite a lack of scientific equipment, Koch ran top corners of the papers (and are thereby able to carry a logo or a painstaking trials out of his home on possible routes of transmission. favorite design) have come on the market. And you can still readily buy In 1876 he packed up his slides and took the train to Breslau (then in T-pins, owl clips, binder clips and ideal clips. Taken together, they have Germany) to present convincing evidence to a packed room of skeptical even made some inroads in the traditional Gem paper clip business. experts that spores shed by the bacterial rods (now known as Bacillus But before you send a sketch of your new, improved design to Gem anthracis) could survive in dirt and launch infections in new hosts. Office Products, consider this: the Gem paper clip can scratch or tear Proceeding from that knowledge, Louis Pasteur in France, on whose paper, catches on others of its kind in a box and, if spread too wide, work Koch had built, created an anthrax vaccine within four years.

) slips off the papers it is intended to hold. The company once estimated In a historical moment, medical science changed. Bolstered by that it received at least 10 letters a month suggesting alternative similar successes against tuberculosis and cholera, the new model anthrax designs. Yet to most people, the Gem simply is the paper clip. It’s as replaced the prevailing view that diseases were spontaneously nc. ( frozen into office culture as the “qwerty” keyboard. —Peter Brown generated (by forces unknown—vengeful gods, perhaps). Diseases were finally better thought of as the signature of contaminants and pathogenic interlopers. Unfortunately, starting in the 1930s, various nations’ experimental adaptation of anthrax spores as weapons renewed the dread over the ); Photo researchers, i ancient scourge. An international treaty banned all bioweapons development in 1972, but the Soviet Union at least seems to have paper clips paper continued to work on anthrax weaponization for some years. Then came the unsolved mail-based post-9/11 anthrax attacks of 2001. They sent vaccine labs in the U.S. into heavy production mode, and researchers burned through some five billion R&D dollars trying to george retseck ( get ahead of what the Centers for Disease Control and Prevention call a “class A” agent—the bioterror category deemed the highest threat to public health. Scientific knowledge can thus take life or give it, depending on whether it is in the hands of a brilliant loner with grace or a brilliant loner with grievances. —Bruce Grierson

www.ScientificAmerican.com SCIENTIFIC AMERICAN 69 © 2009 SCIENTIFIC AMERICAN, INC. © 2009 SCIENTIFIC AMERICAN, INC. origins Intermittent Windshield Wipers A now routine automotive feature pitted an individual inventor against the entire industry

he origins of even the simplest technology are sometimes best and-die company to which Kearns had licensed his patent rights— and it remembered not for the ingenuity of the inventor’s imagination subsequently developed its own system. Tbut rather for the endless legal disputes it engendered. In the In 1976 Kearns, then working with the National Bureau of Stan- annals of famous patent litigation, the intermittent windshield wiper dards, disassembled a commercial wiper system and discovered that holds a pride of place. The genesis of this useful but seemingly incidental the company had apparently adopted his own design. He promptly had feature of the modern automobile even attracted Hollywood scriptwriters a nervous breakdown and, once recovered, began a struggle that lasted in search of a latter-day David and Goliath tale that became a 2008 until the 1990s to gain redress. Kearns recruited several of his children release called Flash of Genius. to help in preparing lawsuits against the world’s major auto companies, The story revolves around a brilliant, idiosyncratic college professor sometimes even serving as his own legal counsel. Juries ultimately named Robert Kearns. Almost blinded by a champagne cork on his determined that Ford and Chrysler had infringed Kearns’s patents, wedding night in 1953, Kearns later found that the monotonous back- resulting in about $30 million in awards. and-forth movement of wiper blades vexed his diminished vision, as Critics have argued that Kearns’s inventions violated a key criterion of recounted in the most commonly cited version of events. patentability, that an invention should not be “obvious” to one skilled in Kearns used off-the-shelf electronic parts in 1963 to devise windshield making widgets similar to the type being patented. An electronic timer— wipers that would clean the surface and then pause. The engineer dem- the essence of Kearns’s invention—was, if anything, obvious, Ford onstrated his system to Ford and ended up revealing details of how it contended. Still, Kearns prevailed in these two cases (but not later ones), worked. The automaker decided not to buy wipers from a Detroit tool- and he will live on indefinitely as a hero to small inventors. —Gary Stix The Eye What was half an eye good for? Quite a lot, actually

ne of creationists’ favorite arguments is that so intricate a device function is probably just to measure the dim ambient light in the deep, as the eye—with a light-regulating iris, a focusing lens, a layered muddy seabeds where hagfish live. Oretina of photosensitive cells, and so on—could not have arisen Our eyes are thus likely to have evolved after our lineages diverged from from Darwinian evolution. How could random mutations have spontaneous- those of hagfish, perhaps 550 million years ago, according to Lamb. Earlier ly created and assembled parts that would have had no independent pur- animals might have had patches of light-sensitive cells on their brain to tell pose? “What good is half an eye?” the creationists sneer, claiming the light from dark and night from day. If those patches had re-formed into organ as prima facie proof of the existence of God. pouchlike structures as in hagfish, however, the animals could have distin- Indeed, even Charles Darwin acknowledged in On the Origin of Species guished the direction from which light was coming. Further small improve- that the eye seemed to pose an objection to his theory. Yet by looking at the ments would have enabled the visualization of rough images, as do the fossil record, at the stages of embryonic development and at the diverse pinhole-camera eyes of the nautilus, a mollusk. Lenses could eventually types of eyes in existing animals, biologists since Darwin have outlined have evolved from thickened layers of transparent skin. The key is that incremental evolutionary steps that may have led to the eye as we know it. at every stage, the “incomplete” eye offered survival advantages over The basic structure of our eyes is similar in all vertebrates, even lam- its predecessors. preys, whose ancestors branched away from ours about 500 million years All these changes may have appeared within just 100,000 generations,

ago. By that time, therefore, all the basic features of the eye must have biologists have calculated, which in geologic terms is the blink of an eye. Getty Images existed, says Trevor Lamb of the Australian National University. But verte- Such speedy evolution may have been necessary, because many invertebrates’ next closest kin, the slippery hagfish—animals with a cartilaginous brates were developing their own kinds of eyes. “There was a real arms cranium but no other bones—has only rudimentary eyes. They are conical race,” Lamb says. “As soon as somebody had eyes and started eating you, it

structures under the skin, with no cornea, no lens and no muscles, whose became important to escape them.” —Davide Castelvecchi FabriceLerouge

he oral contraceptive so universally embraced it became known simply as “the pill” was a decades-long dream of family-plan- Tning advocate Margaret Sanger, although none of the men who realized her vision started out with that purpose. In the 1930s scientists began discovering the roles of steroid hormones in the body and contemplated their therapeutic potential, but extracting hormones from animals was prohibitively expensive for most medical uses. Then, in 1939, Penn State chemist Russell Marker devised a method for making steroids from plants that remains the basis of hormone production even today. The company he founded, Syntex, soon developed an Diamond injectable synthetic progesterone derived from a wild yam. Progesterone was an attractive drug candidate for treating men- Its hardness is natural; strual irregularities that contributed to infertility because its natural role is to prevent ovulation during pregnancy and parts of a woman’s its value is not menstrual cycle. In 1951 Syntex chemist Carl Djerassi—who would later become famous for his prodigious literary output—synthesized a diamond is forever. So are sapphire, silica and Styrofoam. It is plant-derived progestin that could be taken in convenient oral form. the hardest known naturally occurring substance, which When Sanger and her wealthy benefactor, Katharine Dexter McCor- Aexplains why diamonds are excellent industrial cutting mick, approached steroid researcher Gregory Pincus about creating a materials, not emblems of romance. They are no more rare than any contraceptive pill in 1953, he was working for the small and struggling number of minerals, no more dazzling. So although diamonds may have Worcester Foundation for Experimental Biology in Massachusetts. But 20 their genesis in the heat and pressure of the earth’s mantle billions of years earlier at Harvard University, Pincus had scandalized polite society years ago, what a diamond represents is a very modern tale. by carrying out successful in vitro fertilization of rabbits; Sanger believed In 1870 British mining efforts in South Africa uncovered massive he had the daring and know-how to produce her long-sought pill. diamond deposits. Until then, as commodities, diamonds had been Pincus in turn recruited an infertility doctor, John Rock, who was extremely rare; the new finds threatened to flood the market with already using progesterone to suspend his patients’ ovulation for a few stones and obliterate their price. Investors in the mines realized months in the hope that their fertility would rebound. Still under the they had to consolidate their interests to control the flow of diamonds guise of fertility research, Rock and Pincus conducted their first human into the open market, and so in 1888 they formed the De Beers trial in 1954, injecting 50 women with synthetic progestins over the Consolidated Mines Ltd. consortium. By stockpiling its goods to keep course of three months. All 50 stopped ovulating for the duration of the prices high, De Beers controlled the worldwide diamond supply for trial and resumed when the drugs were withdrawn. After several more the next century. years of experimentation, the first contraceptive pill was approved by Its next trick was to control demand. In 1938 De Beers hired the the U.S. Food and Drug Administration in June 1960. —Christine Soares American public-relations firm N. W. Ayer to begin the first advertising campaign that aimed not to sell a specific item, nor to bring customers into a specific store, but rather to sell an idea: that a diamond is the only acceptable symbol of everlasting love—and the larger the diamond, the greater the love. The company planted stories in newspapers and magazines that emphasized the size of the diamonds movie stars

) gave one another; four-color advertisements of celebrities conspicuous- ly flashing their rocks helped to cement the connection. The slogan “A Diamond Is Forever” entered the lexicon in 1949, and by the time the postwar generation grew old enough to wed, the diamond engagement birth-control pills birth-control ring had become a nonnegotiable symbol of courtship and prestige.

orbis ( Antitrust rulings earlier this decade broke De Beers’s choke hold on ); C the diamond market and forced an end to its practice of stockpiling. Yet it has effectively been replaced by Alrosa, a firm 90 percent owned by diamond ( the Russian government that became the world’s largest diamond producer earlier this year. Alrosa, worried about a drop in prices during

GettyImages a global recession, has not sold a stone on the open market since

All December 2008. As Andrei V. Polyakov, a spokesperson for Alrosa, explained to the New York Times, “If you don’t support the price, a

DonFarr diamond becomes a mere piece of carbon.” —Michael Moyer

www.ScientificAmerican.com SCIENTIFIC AMERICAN 71 © 2009 SCIENTIFIC AMERICAN, INC. © 2009 SCIENTIFIC AMERICAN, INC. origins the meChaniCal loom Programmable textile machinery provided inspiration for the player piano and the early computer

master weaver in 18th-century Lyon, ing. The loom would read the arrangement of play a Bach toccata, while another would play a France, Jean-Charles Jacquard was holes punched on a card with a lattice of spring- Gershwin rag. Vastly greater was the versatility aable to fabricate no more than six activated pins connected to hooks that would inside a computer, as 19th-century British scientist inches of silk brocade a week. Even that produc- each individually lift a warp thread wherever a Charles Babbage imagined with his unbuilt Analyti- tion rate was feasible only with the aid of an pin entered a hole. In this way, the loom could be cal Engine and as American engineer Howard apprentice to sit atop his wooden drawloom, programmed, and patterns could be modifi ed or Aiken realized in the 1930s when he constructed raising individual warp threads by hand while the switched by rearranging or replacing the card deck. the Harvard Mark I at IBM. Following Babbage’s maître slid through brightly colored threads of Patented in 1804, an expertly operated Jac- lead, Aiken made stacks of Jacquard punch cards weft. The unrelenting tedium of weaving a quard loom could produce two feet of brocade a operate in tandem, with one stack setting the pattern line by line may explain why his son, day, a feat impressive enough, given France’s operation applied to read data from another. Joseph-Marie, avoided it even before the French dependence on textile exports, to merit the device In modern computers the cards are gone (as Revolution briefl y put brocade out of fashion. a visit from Napoleon. Yet not even the notorious- are Aiken’s electromechanical switches), but Only after squandering his family inheritance did ly ambitious emperor could have appreciated the computers still embody essentially the same Joseph-Marie reconsider—and even then, in- signifi cance that Jacquard’s invention would have architecture. And although industrial looms are stead of becoming a master weaver, he invented to future generations. no longer manned by masters of the craft such as a machine to save himself the labor. As it turned out, holes punched in paper provid- Jacquard’s father, Joseph-Marie’s innovation brings Jacquard’s key idea was to store brocade pat- ed a ready-made solution for developing any kind even weaving to ever higher levels of effi ciency terns on perforated cards that could be fed of programmable machine. Inside the pneumatic through the computer consoles that control the through the loom, with one card per line of weav- mechanism of a pianola, one punched roll would patterning of modern textiles.—Jonathon Keats

JACQUArd loom, invented as labor-saving equipment and patented in 1804, produces textiles in a mongolian factory during the mid-1960s. Procession of punch cards (left) stores instructions of patterns to be woven.

he story behind the brain-destroying mad cow disease vividly solvents and the extended heating, opting instead to separate the parts illustrates why it’s not a good idea to eat your own species. For in a centrifuge. The elimination of the extra cooking steps apparently Tcattle, cannibalism had nothing to do with survival or grisly enabled prions to persist. rituals and everything to do with economics. Perhaps the first prions came from a cow that spontaneously devel- The first so-called mad cows (the sickness is formally called bovine oped the disease. Or perhaps scrapie, a prion disease of sheep that had spongiform encephalopathy) were identified in 1984 in the U.K. They been endemic in the U.K. for centuries but did not seem to pose a threat were probably infected a few years earlier by eating feed derived from to human health, jumped species to infect bovines. In any case, subse- the parts of sheep, cows and pigs that people avoided—diaphragms, quent rendering of infected cows—and then giving the resulting feed to udders, hooves, spinal cords, brains, and the like. The process of sepa- other cows to eat as a cheap source of protein—amplified the outbreak. rating the ground-up components of slaughtered animals to make The situation echoed the devastation of the Fore people of Papua New feed—and other products such as soap and wax—is called rendering Guinea: when the group practiced cannibalistic funerary rites in the and has existed for hundreds of years. In the mid-20th century in the early 20th century, it spread a fatal prion disease called kuru. U.K., rendering demanded the use of solvents and hours of boiling. The For the cows of the U.K. and elsewhere—the export of contaminated procedures presumably destroyed any pathogens that might have come feed spread the disease globally—the epidemic subsided after regula- from diseased creatures—pathogens that include the prion, a danger- tions banned cannibalistic feed. Animal-health officials last year regis- ous, malformed version of a protein found in all mammals. tered 125 cases worldwide, down from the peak of 37,000 in 1992. The In the 1970s the price of oil rose sharply, shooting up 10-fold by rules came too late to save some 200 people who contracted the human 1980. High crude prices, coupled with stagnant economic times, led form of the ailment—a small number, thankfully, considering that tens renderers to seek ways to cut energy costs. So they did away with the of millions have probably dined on mad cow beef. —Philip Yam

PHOTOSYNTHESIS The reaction that makes the world green is just one of many variants

hen the sun shines, green plants dants of what once break down water to get electrons were symbiotic cyanobacteria. Wand protons, use those particles to All of them use some form turn carbon dioxide into glucose, and vent out of the pigment chlorophyll, oxygen as a waste product. That process is by far sometimes in combination the most complex and widespread of the various with other pigments. Photo- known versions of photosynthesis, all of which synthesis starts when arrays of turn the light of particular wavelengths into chlorophyll molecules absorb a chemical energy. (Studies have even suggested photon and channel its energy that certain single-celled fungi can utilize the toward splitting water.

) highly energetic gamma rays: colonies of such But water is a uniquely hardy

leaves fungi have been found thriving inside the post- molecule to be involved in photosynthesis. ( meltdown nuclear reactor at Chernobyl.) Using Taking electrons from water and giving them water as a photosynthetic reactant instead of enough energy to produce glucose requires two

Getty Images scarcer substances such as hydrogen sulfide separate assemblies of slightly different chloro- o d eventually enabled life to grow and thrive pretty phyll molecules (and an apparatus of more than teria learned to split water. Some evidence much everywhere on the planet. 100 different types of proteins). Simpler forms of suggests that it may have been as early as 3.2 Water-splitting photosynthesis was “invent- photosynthesis use one or the other version, but billion years ago. It surely must have happened at ed” by the ancestors of today’s cyanobacteria, not both. The mystery is, Which one appeared least 2.4 billion years ago, when oxygen shifted

); Vincenzo); Lombar also known as blue-green algae. The organisms first in evolution, and how did the two end up from being a rare gas to being the second most loom that now do this type of photosynthesis, includ- combined? “It’s a question we don’t really know abundant one in the atmosphere—a change ing plants, green algae and at least one animal the answer to,” says Robert Blankenship of without which complex multicellular animals that mages ( (the sea slug Elysia chlorotica), carry organelles Washington University in St. Louis. can formulate scientific questions could never etty I

G called chloroplasts that appear to be the descen- Scientists also do not know when cyanobac- have existed. —Davide Castelvecchi

his paper will prove valuable,” wrote John Herschel in a scientific memorandum on April 23, 1842, noting the effect of “Tsunlight on a sample he had treated with “ferrocyanate of potash.” The light turned the chemical blue, leading Herschel to believe he had found a basis for the invention of color photography. He had not—nor would he live long enough to witness the true usefulness of his discovery. A British astronomer and chemist, Herschel had already played a crucial role in the 1839 invention of the black-and-white salt print—the first photographic negative—by finding a way to fix, or set, the fugitive image with sodium thiosulfate. His obsessive search for other photosensitive chemicals led him to try out everything from vegetable extracts to dog urine, as well as the then new pharmaceutical known as ferrocyanate of potash, a substance now called potassium ferricyanide. The ferrocyanate produced a strong image, particularly when combined with another pharmaceutical called ammonio (ammonium ferric citrate), and the image proved permanent after washing. Herschel dubbed his invention the “cyanotype,” but he was deeply dissatisfied with it, because he could not coax the chemistry to produce a stable positive image—only a negative. Most photographers shared his opinion, shunning the strange cyan hue in favor of conventional exposed to sunlight, then washed in water. The blueprint paper recorded the black-and-white pictures. drawing in reverse, black lines appearing white against a cyan background. Only in 1872, one year after Herschel died, was the cyanotype revived, Occupying the top floors of office buildings where there was ample when the Paris-based Marion and Company renamed his invention “ferro- sunlight, blueprint shops thrived for nearly a century, only gradually phas- prussiate paper” and began marketing it for the replication of architectural ing out Herschel’s chemistry for less labor-intensive processes such as the plans. (Previously, they had been copied by hand, which was expensive and diazo print and the photocopy from the 1950s to the 1970s. Today most prone to human error.) At the 1876 Philadelphia Centennial Exposition, the architectural plans are digitally rendered, and Herschel would have mar- process reached American shores, where it finally met success as the blue- veled at the color gamut of the modern laser printer. Yet he would have print, the first inexpensive means of duplicating documents. All that was been puzzled, given his failed efforts to print in full color, to see that when required was a drawing traced on translucent paper. Pressed against a we want to communicate an innovative new plan, we call it a blueprint and second sheet coated with Herschel’s chemical under glass, the drawing was output it in cyan. —Jonathon Keats

Feathers Barbs became plumes long before birds

took wing—in fact, long before birds ) feather he scaly, green Tyrannosaurus rex of monster movies is history. The feathers were recently found in a fossil belonging to a dinosaur lineage

orbis (

real T. rex was probably covered in a fine feathery fuzz, as were most known as the ornithischians, which diverged from the dinos that would ies, ); C d

— tu Tof the dinosaurs in its family, known as the theropods, which later become theropods 70 million years before the Cretaceous suggesting that S

gave rise to birds. Rich fossil beds in northeastern China have yielded speci- feathers could be a very ancient and widespread feature. blueprint exas ( T mens confirming that a wide variety of strictly earthbound dinosaurs sported The original purpose of plumage might have been simply to provide light- Y ast E ersit

feathers during the Cretaceous period, some 125 million years ago. weight warmth, but the vivid hues and patterns seen in modern birds also play v or ni Studying those fossils along with feather development in modern birds a critical role in mating display. Not all feather colors are produced by pigment, f tate U has allowed researchers to reconstruct the likely steps in feather evolution. however. Nanoscale keratin structures within the feathers trap air and scatter enter C The earliest protofeathers were little more than hollow barbs of keratin, the light of certain wavelengths, depending on their shapes—the dark blues of the the ustin S tough protein that makes up scales, hooves and hair. At some point the Eastern bluebird, for instance, result from twisted air channels and keratin bars. f barbs developed horizontal ridges that separated into filaments, then split Further studies of how these nanostructures self-assemble could yield new tephen F. A courtesyo open vertically, resulting in a tassel-like feather. Long, filamentous tail techniques for making colored and light-emitting materials. —Christine Soares S

social gathering in the Cambrian era, beginning some 540 Because these swimmers used muscle contractions to propel them- million years ago, might have resembled an underwater war selves, having muscles anchored to solid bone would have provided Agame —all life resided in the ocean then and almost every greater strength. The hardened skeleton also offered a more solid creature present would have been wearing some sort of external scaffold for bodies to grow larger and to diversify, adding limbs to armor, complete with spiked helmets. The ancestors of insects and their repertoires. crustaceans wore full exoskeletons, probably made from a mixture of Serving as a massive and highly responsive storage depot for protein and chitin like the shells of modern lobsters. Starfishlike organ- critical minerals, particularly calcium, is a role that likely evolved later isms and mollusks manufactured their body armor from calcium but is now one of the most important functions of human bone. With- carbonate extracted from seawater. Even one fishlike evolutionary out calcium, the heart cannot beat and brain cells cannot fire, so far dead-end, the ostracoderm, managed somehow to swim while en- from being inert, bone is in constant flux between growth and self-de- cased in scales and heavy plates made of true bone—that is, mineral- molition to meet the body’s needs and to maintain its own structure. ized cartilage rich in calcium and phosphates. Cells called osteoclasts (“bone breakers”) destroy old or dead bone It was the mild-mannered softies of the period, however, that tissue, and osteoblasts (“bone growers”) give rise to new bone cells. would first develop internal bones. Wormlike organisms, such as the Working together, these cells replace about 10 percent of the skeleton conodonts [see “Teeth,” on page 75], started to mineralize the carti- every year. In the shorter term, if blood calcium levels are too low, lage surrounding their primitive spinal cords, becoming the first verte- osteoclasts destroy bone to release the mineral. Conversely, if exercise brates. Bony cranial coverings came next, and other creatures with produces larger muscles, osteoblasts get to work building new bone to more extensive cartilaginous internal skeletons soon followed suit. withstand their pull. —Christine Soares AIDS and HIV The viral infection’s origin among apes might hold a key for someday taming it

cquired immunodeficiency syndrome tor was likely a virus that has been infecting (AIDS) received its utilitarian name West African chimpanzees since 1492, accord- Ain 1982, a year after U.S. doctors ing to another recent molecular clock study. If recognized an epidemic of pneumonias, rare so, many rural people were surely exposed to cancers and assorted bacterial infections simian immunodeficiency syndrome (SIV) over among mostly male, mostly young and mostly the centuries through live chimps or in bush previously healthy adults. The next year French meat before the infection caught hold in the researchers isolated the cause of the immune human population. Scientists are consequently system collapse that defined the syndrome: a keen to figure out what allowed “successful” virus that selectively infects and destroys SIV strains to adapt to our species and begin immune cells themselves. spreading as HIV. The human immunodeficiency virus (HIV), AIDS researchers are also intensively study- which today resides in more than 30 million ing the behavior of SIV in its native host be- people and seemed to come out of the blue in cause although the simian virus is nearly identi- the early 1980s, is now known to have been cal to HIV, in wild chimps it is generally benign. infecting humans for at least a century. Recent The immune cells of our closest primate cousins studies of preserved tissue samples show HIV get infected, too, but eventually manage to rally present in the former Belgian Congo in 1959, in and reconstitute their numbers. The origin of Haiti by 1966 and possibly in the U.S. as early the devastating syndrome that is AIDS therefore as 1969. The historic specimens also let scien- lies in some combination of minute changes in tists calibrate “molecular clocks” to trace the HIV itself—and the human body’s responses to nc. I evolution of the virus back to its first appear- it—and remains a mystery. —Christine Soares ance in humans. Those analyses place the emergence of the newly formed HIV particle buds from a cell esearchers, R most widespread HIV strain, known as group M, membrane. The virus hijacks immune cells oto oto

PH in southern Cameroon around 1908. Its ances- to copy itself, killing them in the process.

www.ScientificAmerican.com SCIENTIFIC AMERICAN 75 © 2009 SCIENTIFIC AMERICAN, INC. origins Religious Thought Belief in the supernatural may have emerged from the most basic components of human cognition

od may or may not exist, but His followers certainly do. Nearly author of The Black Swan and a professor of risk engineering, calls this every civilization worships some variety of supernatural power, the “narrative fallacy”—we invent cause-and-effect stories to explain Gwhich suggests that humans are hard-wired to believe in the world around us even if chance has dictated our circumstances. something that, by definition, is not of this world. But why? Evolutionari- Gods, empowered with omnipotence and shielded from natural inquiry, ly speaking, how could belief in something in the absence of physical can be used to explain any mysterious event. evidence have aided the survival of early Homo sapiens? Finally, humans can imagine the thoughts and intentions of others Evolutionary biologists Stephen Jay Gould and Richard Lewontin of and imagine that they are different from our own, a trait known as Harvard University proposed that religious thinking is a side effect of theory of mind. The condition, which is severely diminished in autistic tendencies that more concretely help humans to thrive. Perhaps the children, is so fundamental to what it is to be human that it might be a most primitive is our “agency detector,” the ability to infer the presence necessary precondition for civilization. It is a small step from imagining of others. If the grass rustles in the distance, our first instinct is that the mind of another person—even if you have no direct access to it—to someone or something may be lurking. This propensity has obvious imagining the mind of a deity. evolutionary advantages: if we are right, we have just alerted ourselves Taken together, the evolutionary adaptations that made the garden to a nearby predator. (And if we are wrong, no harm done and we can of human society flourish also provided fertile ground for belief in God. get back to picking berries.) Of course, it is impossible to transport ourselves back to early civilization In addition, humans instinctually construct narratives to make sense to rigorously test these ideas, so perhaps one more idea about the divine of what may be a disconnected jumble of events. Nassim Nicholas Taleb, will have to wait for verification. —Michael Moyer

Recorded Music The first recordings remained silent for 150 years

n the ninth century Persian scholars invented the first quaint footnote, but his basic architecture of a horn, known mechanical instrument, a hydropowered organ diaphragm, stylus and cylinder provided the foundation Ithat played music preprinted onto a rotating cylinder. for all sound recording for the next 70 years. In 1874 It would be 1,000 years before inventors cracked the Alexander Graham Bell experimented with sound record- reverse process—printing sounds onto a storage device. ing using de Martinville’s architecture, except he used a The first machine that could pull music from the air cadaver’s ear. He abandoned his efforts to focus on the was Édouard-Léon Scott de Martinville’s phonauto- telephone, which he introduced in 1876. A year later graph, which he introduced in 1857. The device used a Thomas A. Edison (right) was experimenting with a way horn to focus sound waves and direct them onto a small to record sounds made by Bell’s telephone when he diaphragm; attached to the diaphragm was a stylus that shifted efforts to record sounds in the air. His setup was scratched a record of the waves onto a soot-stained almost identical to de Martinville’s except that Edison rotating glass cylinder. The device showed that sound used tin foil as his recording surface, which allowed for recording was possible, but it remained a historic curios- playback. He brought the phonograph to the offices of ity for a simple reason: it could not play back the record- Scientific American in December 1877, the same month ed songs. (At least not until last year, when researchers he patented the device. We wrote, “No matter how at Lawrence Berkeley National Laboratory deciphered familiar a person may be with modern machinery and its

the scratches and played an 1860 recording of a woman wonderful performances ... it is impossible to listen to collection granger singing Au Clair de la Lune.) the mechanical speech without his experiencing the idea De Martinville’s phonoautograph has remained a that his senses are deceiving him.” —Michael Moyer

ooking for the perfect blue? You’ll have to specify. Cobalt, Prus- eval painter’s sian, azurite or ultramarine? According to Philip Ball’s book Bright patron who lEarth, if you were an artist living in the 14th century, the fi nest could afford a blue could cost you a king’s ransom. We can’t even reproduce it in this Virgin in ultra- magazine—it’s not part of the gamut, or achievable range of colors, that marine was display- can be rendered by the four “process colors” of ordinary printing. ing the piety of an arch- The oldest man-made blue—the oldest synthetic pigment, period— bishop and the wealth of a is “Egyptian” blue. Color makers fi red a mixture of one part lime, one modern hedge-fund manager. part copper oxide and four parts quartz in a kiln, which left an opaque As late as 1800, despite blue material that can be ground to a fi ne powder for making paint. The several alternative blues, artists were stuff occurs on Egyptian artifacts dating to around 2500 B.C. and was still seeking a less costly substitute to ultramarine. In 1824 still in use when Mount Vesuvius buried Pompeii in A.D. 79. the French Society for the Encouragement of National Industry offered In the Middle Ages color became central to the alchemists’ obses- 6,000 francs for an industrial process that could make a synthetic sion with transmutation. And the alchemists’ great contribution to ultramarine for less than 300 francs a kilogram. A color manufacturer artists’ blue was ultramarine. It is made from blue lapis lazuli, a semi- named Jean-Baptiste Guimet claimed the prize, and by the 1870s the Getty Images precious stone then mined in Afghanistan. The costly raw material and snob appeal of the natural pigment had died out—killed by time and a elaborate preparation—which involved endless kneading of the lapis price between 100 and 2,500 times higher than the synthetic variety. powder and washing in lye—led to the deep, rich, dark blue seen, as Industrial ultramarine became the blue of choice in the work of Impres-

sUsannaPrice Ball points out, in paintings of the robe of the Virgin Mary. The medi- sionists such as Renoir, Cézanne and van Gogh. —Peter Brown

inTernal-coMbusTion engine Still powering the world’s vehicle fl eet 130 years on

early every vehicle on the road today is start and did not have gears to shift, both of powered by some version of the four-stroke which made gas-powered vehicles of the ninternal-combustion engine patented by day as user-friendly as heavy machinery. Nikolaus Otto in 1876 (right). Otto exploited the Electric vehicles were more suited to the fi ndings of French physicist Sadi Carnot, who in 1824 world of the 19th century than the 20th, showed that the effi ciency of an engine depends however. Those early vehicles could go all critically on the temperature differential between a day on one charge because speed limits hot “source” of energy and a cold “sink.” The four- were set between seven to 12 miles per stroke engine compresses an air-fuel mixture and hour to accommodate horse-drawn ignites it with a spark, thus creating a fl eeting but carriages. When those limits rose intense source of heat. Its portable effi ciency has not after World War I and travel been matched since. between cities and towns became Yet some consider the internal-combustion engine the norm, gasoline-powered an anachronism, a dangerously out-of-date vestige of vehicles began to dominate the a world that assumed oil was unlimited and the auto market. climate stable. The best hope for displacing the Since then, automakers have engine appears to be an electric motor powered by an invested untold billions into energy store such as chemical batteries or a increasing the effi ciency of the hydrogen-powered fuel cell. What many forget is that modern four-stroke engine. Until electric vehicles had their chance—indeed, they were electric cars can surpass the power

Photo Researchers, Inc. far more popular than gasoline-powered cars in the and range of vehicles afforded by gas, late 19th and early 20th century. They could go all expect the internal-combustion day on a single charge and move a driver around a engine to continue its long reign.

sHeilaterry city with ease. They did not require a hand crank to —Michael Moyer

wo eyes positioned above Two features, though, do separate human a pair of nostrils that are facial expressions from those of the rest of the Tthemselves perched above primate pack. First, we have distinctive sclerae, a mouth—such is the layout of the or whites, around our irises. Second, our lips face for vertebrate creatures ranging protrude from our faces and are darker than the from sharks to humans. However well surrounding skin. These traits provide our that arrangement may be optimized for countenances with strong visual contrasts that finding and eating food, among mam- may well better telegraph our feelings. mals the face has taken on another Exactly when and how humans evolved critical role: communication. Nowhere such animated faces is unknown, but clues is this function more apparent than in might be found in the fossilized skulls of our the human visage. ancestors. Endocasts—casts of the impression Primates in general have complex the brain leaves on the interior of the skull—of- social lives, and they commonly use facial fer insights into the changing capabilities of expressions in their interactions with one brain regions over time. In 2000 paleoneurolo- another. We humans have particularly gist Dean Falk, now at Florida State University, expressive faces with which we convey led an analysis of endocasts from the ancient such emotions as fear, happiness, sadness hominid Australopithecus africanus, which lived and anger. Researchers once chalked up the between three million and two million years rich repertoire of human expressions to our ago. The results showed that parts of that having uniquely specialized facial muscles. creature’s anterior temporal region were larger But physical anthropologist Anne Burrows of than those of apes. That enhancement might Getty Images Duquesne University has found that, in fact, have made this human predecessor better at the chimpanzee—the next most dramatic processing information about visages. If so, our

primate—differs little from humans in the propensity for making and reading faces may h erington musculature of its mug. have very deep roots indeed. —Kate Wong Jason Het Jason

Gamma Rays To create one typically means you have to destroy something, be it a single particle or an entire star

amma rays are like cheetahs: they are the charismatic megafauna classified as gamma rays, even the rare ones of less than 100 keV.) As of the particle world. They are light of the maximum possible extreme as these processes may be, we bask in their glow every day: Gpotency, usually defined as a wavelength shorter than 10 –11 sunlight started off as gamma radiation in the sun’s core and degraded into meter—a realm where light’s wave nature is hard to observe and its partic- visible light during its tortuous passage through the overlying layers of gas. ulate nature stands out. Each gamma photon has an energy of more than The gammas of greatest interest to astronomers, though, come from 100 kilo-electron-volts (keV), 100,000 times more than a photon of visible things that are dead, dying or deadly. When a massive star blows up in a light. The mightiest gamma ever recorded packed a punch of 100 tera- supernova explosion, its debris sparkles with gamma rays, and the stellar electron-volts (TeV), far outgunning anything particle physicists can blast corpse left behind—a neutron star or black hole—has such intense gravity out with their most powerful instrument, the Large Hadron Collider. that it drives the ongoing generation of gammas. At the centers of galax- Creating such extreme particles takes commensurately extreme pro- ies, black holes with the mass of a billion stars suck in material, some of cesses: the collision of particles moving at nearly the speed of light; the which does not fall all the way in but squirts back out as jets that set off annihilation of matter and antimatter, which converts their mass entirely shock waves and generate gammas. Some gammas have yet to be traced to into energy, per Einstein’s famous equation E = mc2; the leakage of energy a source and might come from the decay or annihilation of particles not yet out of black holes; and the release of nuclear energy in radioactive decay or known to science. If the starry night sky seems tranquil and gentle, gamma fusion reactions. (Technically, all photons emitted by atomic nuclei are rays betray the true violence of the universe. —George Musser

n the book of Genesis, all God had to do was say the word. In modern cosmology, the creation of light took Irather more effort. The familiar qualities of light—an electromagnetic wave, a stream of particles called pho- Chocolate tons, a source of information about the world—emerged in stages over the first millennia of cosmic history. Mixing the bitter treat In the very earliest moments, electromagnetism did not operate as an independent force but was interwoven with milk was the with the weak nuclear force that governs radioactive decay. Those combined electroweak forces produced a popular breakthrough phenomenon recognizable as light, but more complicated. For instance, there was not one but two forms of ur-light, made up of particles known as B and W bosons. By 10–11 hocolate was a favorite drink of the Maya, the Aztecs and other second, the universe had cooled enough for electromag- Mesoamerican peoples long before the Spaniards “discovered” it and brought it back to Europe. Archaeological evidence netism to make a clean break from the weak force, and the C suggests that chocolate has been consumed for at least 3,100 years and bosons reconfigured themselves to give rise to photons. not just as food: the Maya and other pre-Columbian cultures offered The photons were thoroughly mixed in with material cacao pods to the gods in a variety of rituals, including some that particles such as quarks. Together they formed an undif- involved human sacrifice. ferentiated soup. Had you been alive, you would have But it was an Irish Protestant man who had what might be the most seen a blinding, featureless glow all around you. Lacking pivotal idea in chocolate history. In the 1680s Hans Sloane, a physician color or brightness variations, it was as unilluminating as and naturalist whose estate—a vast collection of books and natural absolute darkness. The first objects with some internal specimens—kick-started the British Museum, was in service to the structure did not emerge until 10 microseconds, when British governor of Jamaica, collecting human artifacts and document- quarks agglomerated into protons and neutrons, and 10 ing local plants and animals. Sloane realized that the bitter local choco- milliseconds, when protons and neutrons began to form late beverage would become much more palatable to his taste when atomic nuclei. Only then did matter start to leave a dis- mixed with milk. He later patented his invention. Although many had tinctive imprint on light. been enjoying chocolate made with hot water, Sloane’s version quickly At about 380,000 years, the soup broke up and light became popular back in England and elsewhere in Europe. Milk also streamed across space in more or less straight lines. At became a favorite addition to solid chocolate, and today around two last it could illuminate objects and form images. As this thirds of Americans say they prefer milk chocolate to dark chocolate. primordial light dimmed and reddened, the universe Chocolate’s positive health effects are by now well documented. passed through a gloomy period known as the Dark Ages. Antioxidants such as polyphenols and flavonoids make up as much as Finally, at an age of 300 million years or so, the first stars 8 percent of a cacao bean’s dry weight, says Joe Vinson, a chemist at lit up and the universe became able to generate new the University of Scranton. Antioxidants neutralize highly reactive light. In Genesis, light emerged before matter, but in molecules called free radicals that would otherwise damage cells. And

it is not a coincidence that the cacao tree (and other antioxidant-rich ) physics, the two emerged together. —George Musser plants such as coffee and tea) would originate from low latitudes.

“Things that have high levels of antioxidants tend to grow in places chocolate near the equator, with lots of sun,” Vinson says. The sun’s ultraviolet rays break up biological molecules into free radicals, and these plants mages (

may produce antioxidants to better endure the stress. etty I ); G

Although eating too much chocolate results in excessive calorie sun intake, human and animal studies have shown that moderate chocolate ( consumption can have beneficial effects on blood pressure, slow down

atherosclerosis and lower “bad” cholesterol. Chocolate may also Getty Images be good for the mind: a recent study in Norway found that elderly men consuming chocolate, wine or tea—all flavonoid-rich foods— llinor Hall Hall llinor performed better on cognitive tests. —Davide Castelvecchi E

www.ScientificAmerican.com SCIENTIFIC AMERICAN 79 © 2009 SCIENTIFIC AMERICAN, INC. © 2009 SCIENTIFIC AMERICAN, INC. origins Cupcakes The yummy baked good is one of America’s first and finest contributions to world cuisine

ike many acts of pure genius, the invention of the cupcake is lost in the creamy fillings of history. According to food historian LAndrew Smith, the first known recipe using the term “cupcake” appeared in an American cookbook in 1826. The “cup” referred not to the shape of the cake but to the quantity of ingredients; it was simply a downsized English pound cake. Lynne Olver, who maintains a Web site called the Food Timeline, has tracked down a recipe for cakes baked in cups from 1796. But we will probably never know the name of the first cook to take the innovative leap or whether it had anything to do with a six-year-old’s birthday party. “Just like other popular foods—the brown- ie comes to mind—it’s impossible to pinpoint a date of origin for the cupcake,” says culinary historian Andrea Broomfield. That cook almost certainly lived on the left bank of the Atlantic. Broomfield says that the earliest known cupcake recipes in England date Appendix to the 1850s and that their popularization was slow. One writer in 1894 had evidently never heard of cupcakes: “In Miss [Mary E.] Wilkins’s Not needed, but not useless delightful New England Stories, and in other tales relating to this corner of the United States, I have frequently found mention of cup-cake, a any have speculated that it exists to keep surgeons in busi- dainty unknown, I think, in this country. Will some friendly reader ... on ness. Leonardo da Vinci thought it might be an outlet for the other side of the Atlantic kindly answer this query, and initiate an M“excessive wind” to prevent the intestines from bursting. The English lover of New England folks and ways into the mysteries of great artist and anatomist was not entirely off base in that the human cup-cake?” Even to this day true cupcakes—as opposed to muffins or appendix does appear to have originated at a time when primates ate cakes cut up into cup-size portions—are sadly uncommon in Europe. plants exclusively, and all that fiber was tougher to digest. In recent years the U.S. has had something of a great cupcake The intestinal offshoot formally known as the vermiform appendix awakening, as blogs and bakeries have devoted themselves to its is a long, slender cavity, closed at its tip. It branches off the cecum, pleasures. Some attribute this renewed popularity to the cupcake-in- which is itself a big pouch at the beginning of the large intestine that dulging characters of HBO’s Sex and the City, and food historian Susan receives partly digested food emptying from the small intestine. While Purdy also credits dietary awareness: you can have your low-calorie food stalls in the cul de sac of the cecum, friendly gut microbes help to cake and eat it, too. But true connoisseurs needed no moment of redis- break it down further. Some of today’s herbivorous animals, such as covery. They never forgot what it was like to be six. —George Musser rabbits and koalas, have a large appendix, filled with specialized cellulose-digesting bacteria for the same purpose. Yet plenty of plant- eating mammals, including some monkeys, have no appendix at all, relying on an enlarged cecum to break down plants. Because the appendix seems to be optional even among primates, biologists cannot ) simply infer that ours is a shrunken legacy from a common ancestor appendix with the bunny. Rather the primate appendix and the appendices of ( other herbivorous mammals appear to have evolved independently as extensions of the cecum—perhaps for the same digestive purpose— but the human appendix has long since lost that function.

Serving as a repository for food and benign digestive bugs, though, Photo Researchers, Inc. may have created a secondary role for the appendix, at least early in

life. Its inner lining is rich in immune cells that monitor the intestinal amazine environment. During the initial weeks of infancy, the human gut is first C cott populated with its normal, healthy complement of symbiotic microbes; S ); the appendix may be a training center to help naive immune cells learn

to identify pathogens and tolerate harmless microbes. If it hasn’t cupcake already been removed in early adulthood, the opening of the appendix cavity closes entirely sometime in middle age. But by that time its mages ( etty I

purpose may have been served. —Christine Soares G

hen Tim Berners-Lee sketched out what we now know as the Information would no longer be stored on hierarchal trees; instead a forest World Wide Web, he offered it as a solution to an age-old but of nodes would be connected by links. “When describing a complex sys- Wprosaic source of problems: documentation. In 1989 the tem,” he wrote, “many people resort to diagrams with circles and arrows.... computer scientist was working at CERN, the particle physics laboratory The system we need is like a diagram of circles and arrows, where circles near Geneva, just as a major project, the Large Electron Positron collider, and arrows can stand for anything.” was coming online. CERN was one of the largest Internet sites in Europe at It was this agnosticism regarding content that gave what became the the time, home to thousands of scientists using a variety of computer Web the power it has today. The system Berners-Lee finished on Christmas systems. Information was stored hierarchically: a treelike central repository Day in 1990 was imbued with flexibility at every level: any file could be held documents at the end of its branches. Finding a file meant crawling up identified by its unique address, or Universal Resource Locator (URL). the trunk and out to the right leaf. Scientists who were new to CERN (and Behind the scenes, the Hypertext Transfer Protocol (HTTP) provided a there were a lot of them—most researchers stayed only for brief, two-year uniform language for different types of computer systems to communicate stints) had a hard time figuring out which branches to venture onto to find with one another. And simple Hypertext Markup Language (HTML) linked the right information for their project. documents together and specified how they should appear. Equally impor- In a proposal to CERN management that March, Berners-Lee suggested tant, the components were made available free of charge to anyone who constructing a system that operated more like the working structure of the wanted them. Two decades later the World Wide Web has proven itself to organization itself: “A multiply connected ‘web’ whose interconnections be the most effective information dissemination platform ever created. evolve with time,” he wrote in Information Management: A Proposal. —Michael Moyer

Tectonic Plates The long, strange trip of continental drift

lfred Wegener’s idea of continental drift wandered sinks back down at deep ocean trenches. In this way, the in the wilderness for the first few decades after he crust and the uppermost, solid portion of the mantle (togeth- Awrote about it in his 1915 book, The Origin of er known as the lithosphere) are divided into moving plates. Continents and Oceans. Although some geologists mar- Hess’s ideas became accepted after studies found the shaled further evidence for the theory, most remained magnetism of rock on the ocean floor matched predictions: skeptical because no plausible mechanism seemed capable the earth’s magnetic field, which sporadically reverses of sending huge landmasses plowing through the ocean polarity, leaves its imprint in solidifying rock, producing crust on long journeys across the surface of the earth. bands of alternating magnetism parallel to ocean ridges. The modern concept of moving tectonic plates emerged Continental drift thus has its roots in the immense heat in 1962, proposed by Harry H. Hess of Princeton University. coming from the planet’s interior. Radioactive decay still Hess had captained a U.S. Navy transport ship during World produces the heat today. Yet scientists estimate that three War II and used the vessel’s sonar to map the Pacific Ocean billion years ago twice as much heat was emerging, leading floor along his travels. He hypothesized that all the earth’s to numerous hotspots with magma welling up, fragmenting crust—oceanic as well as continental—was mobile, driven by the early lithosphere into many small tectonic plates. The convective motions in the underlying layer known as the first continents may have been not much larger than Iceland mantle. New crust forms at mid-ocean ridges, where hot and a lot like it in other ways, too: for 16 million years or magma from the mantle wells up and crystallizes. The so Iceland (below) has been forming above a hotspot young crust spreads from the ridges, and old crust on the Mid-Atlantic Ridge. —Graham P. Collins mages I G etty

Babies’ Brains ■ Naming Life ■ Fictional Reads By kate wong

■➜ The Philosophical Baby: children think can help adults become better Al so Notable What Children’s Minds Tell parents—another subject Gopnik explores. Us about Truth, Love, and NONFICTION ➜ the Meaning of Life ■ Vesuvius: A Biography ➜➜ Darwin’s Armada: Four Voyages and by Alison Gopnik. Farrar, Straus and by Alwyn Scarth. Princeton University the Battle for the Theory of Evolution Giroux, 2009 ($25) Press, 2009 ($29.95) by Iain McCalman. W. W. Norton, 2009 ($29.95) ➜➜ Not a Chimp: The Hunt to Find the Genes that Make Us Human Alison Gopnik, a professor Writer Alwyn Scarth traces the by Jeremy Taylor. Oxford University Press, of psychology at the Universi- violent history of Mount Vesuvi- 2009 ($27.95) ty of California, Berkeley, us—from its destruction of Pompeii ➜➜ The Nature of Technology: What It Is and How It Evolves argues that far from being in A.D. 79 to its most recent erup- by W. Brian Arthur. Free Press, irrational and limited in their tion in 1944. What might the 2009 ($27) ability to think, babies are future hold for this, the most dangerous ➜➜ Smithsonian Atlas of smarter, more imaginative and more con- volcano in all of Europe? Scarth discusses the Space Exploration by Roger D. Launius and Andrew K. Johnston. scious than adults. Along the way, she exam- warning signs of an eruption and considers Bunker Hill Publishing, 2009 ($34.99) ines such fascinating topics as why children current contingency plans for the 600,000 ➜➜ Crow Planet: Essential Wisdom from pretend, how they discover the truth, the people who live in the 236-square-kilometer the Urban Wilderness origins of love and morality, and how early area around the summit of this ferocious by Lyanda Lynn Haupt. Little, Brown, 2009 ($23.99) life shapes later life. Understanding how force of nature. FICTION FOR ADULTS ➜➜ Pythagoras’ Revenge: A Mathematical Excerpt Mystery ➜ Naming Nature: The Clash between Instinct and Science by Arturo Sangalli. Princeton University Press, ■ 2009 ($24.95) by Carol Kaesuk Yoon. W. W. Norton, 2009 ($27.95) ➜➜ Ultimatum by Matthew Glass. Grove/Atlantic, Biologist and journalist Carol Kaesuk Yoon explores humanity’s long- 2009 ($24) standing obsession with naming living things. Here she describes how the modest barnacle—which 16th-century scholars believed came from FICTION FOR kidS plants known as “Barnakle Trees” and themselves concealed miniature ➜➜ The Evolution of Calpurnia Tate geese called barnacle geese—tricked even 18th-century father of system- by Jacqueline Kelly. Henry Holt, atic classification Carl Linnaeus. 2009 ($16.99) ➜➜ “Picture a barnacle. You probably envision something hard, white, salt-encrusted, The Unknowns: A Mystery by Benedict Carey. Amulet Books, 2009 ($16.95) sharp, and stuck onto something else, like a boat bottom. And though they seem more rocklike than lifelike at first glance, at second glance they may begin to remind you of a ) Lucy limpet perhaps, or a mussel, or some other sea creature with a formidable hard outer ( shell, softer more vulnerable parts tucked inside, and zero mobility. The barnacle, most Exhibits people would say, belongs with what are clearly its like kind, the clams, snails and so on; ➜➜ Lucy’s Legacy: The Hidden that is, it would appear to be a mollusk. And this is exactly how Linnaeus ordered it. Treasures of Ethiopia and Titanic: The Artifact “… It was the group he called ‘The Worms.’ So the barnacles fell in, at the master’s Exhibition hand, as they would likely have at any one of ours, with the mollusks. And there barnacles June 24–October 25 at the Discovery Times Square remained, more or less, for another half century or so. HoustonMuseumNatural of Science Exposition in New York City.

“Not that anyone was terribly worried about them. Compared with trumpeting ele- mail S phants or towering oak trees, barnacles were just kind of hard for naturalists to get ➜➜ Farmers, Warriors, Builders: The Hidden worked up about. If there were a living creature whose understanding would shake the Life of Ants very foundations of the ordering of life, the barnacle seems the least likely candidate. But May 30–October 10 at the Smithsonian National Museum of Natural History there was much more to those tiny shuttered creatures than anyone suspected.” in Washington, D.C. CourtesyDeborahof

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VISIT ScientificAmerican.com TO TAKE ADVANTAGE OF ALL THE EASY WAYS TO STAY INFORMED. > www.ScientificAmerican.com/newsletters > www.ScientificAmerican.com/rss > www.ScientificAmerican.com/podcast ScientificAmerican.com > www.ScientificAmerican.com/mobile anti gravity ■ ■ ■ ■ Cache and Carry The best answer yet to what’s black and white and read all over By Steve Mirsky

I’m not your classic “early adopter” when it comes Users can also easily move PDF and text documents over to to new electronic gizardry (a word I just made the device. So instead of printing out the 125 pages of manu- up that means a combination of gizmo and wiz- scripts and proposals that we may go over in a given editorial ardry, with a secondary definition of bird diges- meeting, I just load the whole PDF onto the Kindle. At the meet- tion). I’m not even what one ersatz electronics ing, it’s then a snap to shuttle between the editorial notes and a guru referred to as an “early adapter,” although Dan Jenkins golf novel called Slim and None, which unfortu- I do sometimes wonder if my purpose in life has been reduced to nately also describes the chances that I will read The Brothers making sure my various devices are all plugged in correctly. Karamazov before you read this column. So I’m a bit surprised to be a longtime owner (since February!) But the Kindle is not without its drawbacks. The ease with of a second-generation Amazon Kindle. The e-reader looks both which one can sample a book’s first chapter for free and then buy futuristic and pedestrian, like something Harrison Ford in Blade the complete work can lead the less careful reader astray. That Runner might be reading from and then bleeding on. was how, before a recent flight to London, I wound up getting a My sister, who travels a great deal for work and is fond of air- Dean Koontz best seller called Relentless. The plot was man- plane fiction of the Dan Brown and Robin Cook schools, adopt- bites-dog intriguing: a novelist gets a bad review, after which the ed a first-generation model early. Borrowing hers, I was reviewer appears to be intent on tracking down thus able to experiment when I had some travel of and killing the writer. my own. I usually take a bunch of books on But then (SPOILER ALERT!, although the road. So I weighed the Kindle against the “spoiler” suggests there is something that books—seriously, I put them on a scale—and could be ruined), I unexpectedly de- promptly decided to get one of them there scended into a Bizarro world of good- newfangled, thin, low-mass reading ma- guy survivalists, bad-guy intellectuals chines of my own. and a six-year-old physics supergenius Amazon sells Kindle versions named Milo who actually does read of many new books at a discount. Dostoyevsky, albeit a comic book But one of the first things I discov- edition of Crime and Punishment. I ered is how much stuff you can cram was alternately shaking and scratch- on it that is totally free. Project Guten- ing my head long before Milo builds berg, which is trying to get everything a teleportation apparatus that can’t that’s now off copyright onto the Web, handle the boy’s weight but can deal has posted thousands of classics, and it’s with the 10-pounds-lighter family easy to download them in seconds on a home dog. Which quickly learns how to computer and then move them over to the Kindle. teleport itself without the device. You Three decades ago I bought (but still have not read) know, the way Pavlov’s dogs learned to a copy of The Brothers Karamazov, which sits on a shelf at home. salivate without the food. With his new power, the dog foils a Now, with the Kindle, in less than five months I already have nefarious plot. Woof. not read the electronic edition of The Brothers Karamazov on In the climactic confrontation, Milo saves the day with salt three continents. shakers that he’s converted into localized, short-interval time- (By the way, the 1958 movie version of that book stars a very reversal machines (of the Galaxy Quest Omega 13 variety). The young, very subdued William Shatner, who later, as Captain six-year-old undoes the murder of his father, the novelist, who, Kirk, was often handed a Kindle-looking device, which he then given a second chance, gets the jump on his assailant, the review- invariably glanced at, signed and returned. So rather than being er’s mother, head of a giant conspiracy to lower American cul- h by flynn larsen; illustration by matt collins an e-reader, it was probably a deep-space requisition-generating tural standards. (I’m not kidding, that’s the actual plot.) Which p machine with which to authorize the purchase of red Starfleet leads me to the biggest drawback of the Kindle: at $299, you can’t

shirts, which are tough to keep in stock.) really afford to hurl it into the Thames. ■ Photogra

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