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CLIMATE NEUROSCIENCE BIOLOGY How Feedbacks Growing an Eye How Do Genes for Could Speed Warming in the Lab Autism Spread? ScientificAmerican.com NOVEMBER 2012 The Inner Life of QuarksScience aims to look inside the smallest bits of matter SPECIAL ELECTION REPORT OBAMA & ROMNEY 14 ScienceAnswer Questions © 2012 Scientific American www.diako.ir www.diako.ir ON THE COVER The Standard Model of particle physics holds that quarks (the constituents of protons and neutrons) and leptons (such as the electron) are indivisible. Yet some findings suggest that quarks and leptons actually contain still tinier building blocks, known as preons. If preons exist, they will lead to discoveries of phenomena scientists have yet to imagine. Photograph by Craig Cutler. November 2012 Volume 307, Number 5 42 FEATURES PARTICLE PHYSICS SCIENCE AND SOCIETY 22 The Inner Life of Quarks 48 America’s Science Problem What if the smallest bits of matter actually harbor The U.S. faced down authoritarian governments an undiscovered world of particles? By Don Lincoln on the left and right. The “antiscience” movement is now posing an even greater challenge. NEUROSCIENCE By Shawn Lawrence Otto 30 Grow Your Own Eye Biologists have coaxed cells to form a retina, a step Also: Science in an Election Year Scientific American’s toward growing replacement organs outside the body. editors grade Obama and Romney on their policy acumen. By Yoshiki Sasai BIOLOGY ENVIRONMENT 58 Autism and the Technical Mind 36 Global Warming: Faster Than Expected? Scientists and engineers may be more likely to pass Loss of ice, melting of permafrost and other climate along genes that predispose their children to autism. effects are worrying. By John Carey By Simon Baron-Cohen PALEONTOLOGY QUANTUM PHYSICS 42 The Strangest Bird 62 A New Enlightenment Fossil discoveries reveal the surprising Quantum theory once seemed like the last nail in the coffin evolutionary history of penguins. of pure reason. Now it’s looking like its savior. FRANS LANTING By R. Ewan Fordyce and Daniel T. Ksepka By George Musser November 2012, ScientificAmerican.com 1 www.diako.ir© 2012 Scientific American DEPARTMENTS 4 From the Editor 6 Letters 9 Science Agenda Policy leaders need to prime the economy’s most important engine: science and technology innovation. By the Editors 10 Forum 10 Single genes do not control voting or other complex hu- man behaviors. By Evan Charney and William English 11 Advances An autism pill. A scale for single molecules. Rescue roaches. Robotic surgeons. Why humans are born helpless. 19 The Science of Health Medical imaging offers new ways to pinpoint causes of death. By Maryn McKenna 21 TechnoFiles To track my iPhone thief. By David Pogue 68 Recommended The Higgs boson hunt. A history of drinking water. George Boole and Claude Shannon. Nervous system madness. By Anna Kuchment 12 69 Skeptic Replicating Milgram’s shock experiments reveals deep moral conflict. By Michael Shermer 70 Anti Gravity Evolutionary theory in an election year. By Steve Mirsky 71 50, 100 & 150 Years Ago 76 Graphic Science Disease transmission pathways uncovered. By John Matson ON THE WEB Election 2012: The Science Perspective As the U.S. presidential campaign kicks into high gear, we provide news and analysis about the candidates’ statements and track records on science, technology, the environment and health care. 21 Go to www.ScientificAmerican.com/nov2012/campaign Scientific American (ISSN 0036-8733), Volume 307, Number 5, November 2012, published monthly by Scientific American, a division of Nature America, Inc., 75 Varick Street, 9th Floor, New York, N.Y. 10013-1917. Periodicals postage paid at New York, N.Y., and at additional mailing offices. Canada Post International Publications Mail (Canadian Distribution) Sales Agreement No. 40012504. Canadian BN No. 127387652RT; TVQ1218059275 TQ0001. Publication Mail Agreement #40012504. Return undeliverable mail to Scientific American, P.O. Box 819, Stn Main, Markham, ON L3P 8A2. Individual Subscription rates: 1 year $39.97 (USD), Canada $49.97 (USD), International $61 (USD). Institutional Subscription rates: Schools and Public Libraries: 1 year $72 (USD), Canada $77 (USD), International $84 (USD). Businesses and Colleges/Universities: 1 year $330 (USD), Canada $335 (USD), International $342 (USD). Postmaster: Send address changes to Scientific American, Box 3187, Harlan, Iowa 51537. Reprints available: write Reprint Department, Scientific American, 75 Varick Street, 9th Floor, New York, N.Y. 10013-1917; fax: 646-563-7138; [email protected]. Subscription inquiries: U.S. and Canada (800) 333-1199; other (515) 248-7684. Send e-mail to [email protected]. Printed in U.S.A. Copyright © 2012 by Scientific American, a division of Nature America, Inc. All rights reserved. 2 Scientific American, November 2012 www.diako.ir© 2012 Scientific American www.diako.ir From the Editor Mariette DiChristina is editor in chief of Scientific American.Follow her on Twitter @mdichristina Of Quarks and (Presidential) Men hree quarks for muster mark! to CERN’s Large Hadron Collider near Geneva, scientists hope Sure he hasn’t got much of a bark to find out. And sure any he has it’s all beside the mark. Mysteries drive a lot of science, but we prefer our policy lead- —James Joyce, Finnegans Wake ers’ intentions to be clear. That—and an evidence-based belief that the support of research and innovation has powered hu- TAs he later explained in his 1995 book The Quark manity’s current levels of prosperity—is why Scientific American and the Jaguar, physicist Murray Gell-Mann had the sound of is serving as media partner for an important public discussion. his theorized particle in mind before discovering the spelling We worked with ScienceDebate.org and a host of the na- he would eventually adopt from a book James Joyce published tion’s preeminent scientific organizations, such as the Ameri- in 1939. “The number three fitted perfectly the way quarks oc- can Association for the Advancement of Science, to secure an- cur in nature,” Gell-Mann wrote, referring to how three quarks swers to 14 top scientific questions from presidential candidates make up a proton, itself a component, along with the electron Mitt Romney and Barack Obama. You can read their full an- and neutron, of atoms. Although George Zweig, who also theo- swers at www.ScientificAmerican.com/article.cfm?id=obama- rized this fundamental particle in 1964, preferred the term “ace,” romney-science-debate. (We also sent a subset of the questions quark eventually stuck. to legislators who have key roles in science policy.) Not so, perhaps, the quark’s shared preeminence with the See our Science Agenda “Future Jobs Depend on a Science- lep ton as the most fundamental component of matter. Tanta- Based Economy,” on page 9, for a further discussion of the eco- lizing hints in various experiments point to still smaller con- nomic importance of science and turn to “America’s Science stituents, dubbed preons, in the particle zoo known to physics. Problem,” by science writer Shawn Lawrence Otto, starting on You will learn from “The Inner Life of Quarks,” by Don Lin- page 48, to learn about a troubling issue that could impede our coln, beginning on page 22, that each quark could, in turn, be nation’s progress and to see a report on how well the candi- made of three preons—or perhaps five, depending on which dates answered the questions. We hope you find the results as theory you prefer. By 2014 or 2015, after successive upgrades useful as they are thought-provoking. BOARD OF ADVISERS Leslie C. Aiello David Gross Steven Kyle Carolyn Porco Michael Shermer President, Wenner-Gren Foundation Frederick W. Gluck Professor of Applied Economics and Leader, Cassini Imaging Science Publisher, Skeptic magazine for Anthropological Research Professor of Theoretical Physics, Management, Cornell University Team, and Director, CICLOPS, University of California, Santa Barbara Space Science Institute Michael Snyder Roger Bingham (Nobel Prize in Physics, 2004) Robert S. Langer Professor of Genetics, Stanford Co-Founder and Director, David H. Koch Institute Professor, Vilayanur S. Ramachandran University School of Medicine The Science Network Lene Vestergaard Hau Massachusetts Institute of Technology Director, Center for Mallinckrodt Professor of Brain and Cognition, Michael E. Webber G. Steven Burrill Physics and of Applied Physics, Lawrence Lessig Associate Director, Center for CEO, Burrill & Company University of California, Harvard University Professor, Harvard Law School San Diego International Energy & Environmental Policy, University of Texas at Austin Arthur Caplan Danny Hillis Ernest J. Moniz Director, Division of Medical Ethics, Lisa Randall Co-chairman, Applied Minds Cecil and Ida Green Steven Weinberg Department of Population Health, Professor of Physics, Distinguished Professor, Director, Theory Research Group, NYU Langone Medical Center Daniel M. Kammen Harvard University Massachusetts Institute Department of Physics, Class of 1935 Distinguished Martin Rees George M. Church Professor of Energy, of Technology University of Texas at Austin Director, Center for Computational Professor of Cosmology Energy and Resources Group, and (Nobel Prize in Physics, 1979) Genetics, Harvard Medical School John P. Moore and Astrophysics, Director, Renewable and Appropriate Professor of Microbiology and University of Cambridge George M. Whitesides Rita Colwell Energy Laboratory, University of Immunology, Weill Medical Professor of Chemistry and Distinguished Professor, University