Methane Point to Bacteria on Mars and Titan?
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DO-IT-YOURSELF QUANTUM MECHANICS • LOST MAMMALS REWRITE HISTORY CANCER AND CHROMOSOMES SCIENTIFIC A Radical New Theory MAY 2007 AMERICAN WWW.SCIAM.COM Hazy Hints of Alien Life Does methane point to bacteria on Mars and Titan? Brains beyond Coma Mysteries of the vegetative state Prevent Blackouts Smart power grids reroute themselves Nanotube Nets Better than wires for fl exible electronics COPYRIGHT 2007 SCIENTIFIC AMERICAN, INC. contentsmay 2007 SCIENTIFIC AMERICAN Volume 296 Number 5 features COVER STORY: SPACE SCIENCE 42| The Mystery of Methane on Mars and Titan BY SUSHIL K. ATREYA Could the methane in the atmospheres of Mars and Titan be caused by unusual geologic activity—or life? MEDICINE 52IChromosomal Chaos and Cancer BY PETER DUESBERG Current wisdom on the role of genes in malignancy may not explain some of the features of cancer, but stepping back to look at the bigger picture inside cells reveals a view that just might. ENERGY 60IPreventing Blackouts BY MASSOUD AMIN AND PHILLIP F. SCHEWE A smarter power grid that automatically responds to problems could reduce the rising number of debilitating blackouts. PALEONTOLOGY 68ISouth America’s Missing Mammals BY JOHN J. FLYNN, ANDRÉ R. WYSS AND REYNALDO CHARRIER An unexpected menagerie of unique mammal fossils is overturning long-held ideas about South America’s geologic history. 52 Do faulty chromosomes INFORMATION TECHNOLOGY trigger cancer? 76ICarbon Nanonets Spark New Electronics BY GEORGE GRUNER Random networks of tiny carbon tubes could make possible low-cost, fl exible devices such as “electronic paper” and printable solar cells. NEUROSCIENCE 84IEyes Open, Brain Shut BY STEVEN LAUREYS Brain-imaging techniques yield a better understanding of patients in the vegetative state. PHYSICS 90IA Do-It-Yourself Quantum Eraser BY RACHEL HILLMER AND PAUL KWIAT Carry out a home experiment to illustrate one of the weirdest effects in quantum mechanics. www.sciam.com SCIENTIFIC AMERICAN 5 COPYRIGHT 2007 SCIENTIFIC AMERICAN, INC. SCIENTIFIC AMERICAN Volume 296 Number 5 departments 10 SA Perspectives Even fl awed scientists have good ideas. 12 How to Contact Us 12 On the Web 20 104 14 Letters 18 50, 100 & 150 Years Ago 20 News Scan 40 Insights Saving Amazonia’s indigenous peoples means ■ Three additions to nanotech’s tool kit. not meeting them, insists Sydney Possuelo— ■ Protein folding and “silent mutations.” a policy of noninterference he hopes to extend, ■ Live streaming mobile video. even if others hate it. ■ Ionization via electron tunneling observed. ■ Text-free cell phones for China, Africa and India. 96 Working Knowledge ■ Heart cells power micropumps. Beams of sound. ■ By the Numbers: Agricultural productivity. 98 Reviews ■ Data Points: Data explosion. In two new books, University of Oxford art historian Martin Kemp explores, often brilliantly, the interplay of art and science. 40 Sydney Possuelo, advocate of Brazil’s indigenous people columns 38 Skeptic BY MICHAEL SHERMER How self-deception proves to be more powerful than deception. 39 Sustainable Developments BY JEFFREY D. SACHS Nurturing new technologies is the key to preventing climate change. 102 Anti Gravity BY STEVE MIRSKY Ale’s well with the world. 104 Ask the Experts Where is the universe expanding to? What is “junk” DNA, and what is it worth? Cover image by Ron Miller; photograph at left courtesy of Sydney Possuelo; illustration on page 5 by Kenn Brown. Scientifi c American (ISSN 0036-8733), published monthly by Scientifi c American, Inc., 415 Madison Avenue, New York, N.Y. 10017-1111. Copyright © 2007 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 American, 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., 415 Madison Avenue, New York, N.Y. 10017-1111; (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. 8 SCIENTIFIC AMERICAN MAY 2007 COPYRIGHT 2007 SCIENTIFIC AMERICAN, INC. SA Perspectives When Pariahs Have Good Ideas Even mentioning the name Peter Duesberg in- have dramatic relevance to human affairs: Is there fl ames strong feelings, both pro and con. After gain- strong new hope for curing a disease, transforming the ing fame in 1970 as the virologist who fi rst identifi ed economy, building a better mousetrap? Alternatively, a cancer-causing gene, in the 1980s he became the reporters and editors may gravitate toward new sci- leading scientifi c torchbearer for the so-called AIDS ence that easily inspires the public’s sense of wonder, dissidents who dispute that HIV causes the immuno- as so many astronomy stories do. And reports that ap- defi ciency disorder. To the dissidents, Duesberg is pear in certain major scientifi c journals tend to get Galileo, oppressed for proclaiming scientifi c truth more play because those publications have a self-ful- against biomedical dogma. A far larger number of fi lling reputation for releasing the most noteworthy AIDS activists, physicians and papers. (It doesn’t hurt that those journals have par- researchers, however, think ticularly strong public relations departments, too.) Duesberg has become a crank When we look at submitted manuscripts from sci- who refuses to accept abundant entists, we consider it a reassuring sign when the au- proof that he is wrong. To them, thors forthrightly acknowledge both their collabora- he is at best a nuisance and at tors and their competitors and note potential con- worst a source of dangerous dis- fl icts of interest before we ask. If we see that they are information on public health. describing the science of their rivals fairly, we can Readers may therefore be have more confi dence that they are being similarly shocked to see Duesberg as an candid about their own work. (Still, the old nuclear author in this month’s issue. He disarmament treaty maxim applies: trust, but verify.) is not here because we have mis- We typically steer away from controversial ideas too givings about the HIV-AIDS new to have much supporting evidence. Those that UNORTHODOX cancer theory link. Rather Duesberg has also have lasted for years and accumulated some substan- bears consideration. developed a novel theory about tiation have earned consideration. Our judgments are the origins of cancer, one that imperfect, but they tend to mirror those of the scien- supposes a derangement of the chromosomes, rather tifi c community. than of individual genes, is the spark that ignites ma- Blots on a researcher’s history often should bear lignant changes in cells. That concept is still on the on regard for his or her new work. Scientists who have fringe of cancer research, but laboratories are inves- intentionally published fraudulent papers, as the stem tigating it seriously. Thus, as wrong as Duesberg cell researcher Woo Suk Hwang so notoriously did surely is about HIV, there is at least a chance that he two years ago, may be irredeemably tainted. But to is signifi cantly right about cancer. We consider the dismiss a scientist solely for holding some wrong or Researchers, Inc. Photo case worthy of bringing to your attention, with the controversial views risks sweeping away valuable nug- article beginning on page 52. gets of truth. We respect the opinions of any readers Thousands of scientifi c papers appear in technical who may criticize our choice to publish Duesberg in journals every month; why do some rate more fame this case but hope they will nonetheless evaluate his and journalistic attention? It helps for science news to ideas about cancer on their own merits. STEVE GSCHMEISSNER THE EDITORS [email protected] 10 SCIENTIFIC AMERICAN MAY 2007 COPYRIGHT 2007 SCIENTIFIC AMERICAN, INC. 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