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CANCER-KILLING VIRUSES • DANGEROUS MELTING IN THE ARCTIC China: The Next Space Superpower OCTOBER 2003 $4.95 WWW.SCIAM.COM Star Clusters Born of Galactic Collisions The Economics of Child Labor Protecting Farms against Agricultural Terrorism —see page 20 COPYRIGHT 2003 SCIENTIFIC AMERICAN, INC. october 2003 contentsSCIENTIFIC AMERICAN Volume 289 Number 4 features ASTRONOMY 46 The Unexpected Youth of Globular Clusters BY STEPHEN E. ZEPF AND KEITH M. ASHMAN Globular star clusters were thought to be the stodgy old codgers of the universe, but many, in fact, are young. MATERIALS 52 Artificial Muscles BY STEVEN ASHLEY New polymers that act like electrically controlled muscles could power robots and prosthetic limbs, replace speaker diaphragms and literally change the shape of aviation. ENVIRONMENT 60 Meltdown in the North BY MATTHEW STURM, DONALD K. PEROVICH AND MARK C. SERREZE Sea ice and glaciers are melting, permafrost is thawing, tundra is yielding to shrubs. How will it all affect the Arctic—and the rest of the planet? BIOTECHNOLOGY 68 Tumor-Busting Viruses BY DIRK M. NETTELBECK AND DAVID T. CURIEL Researchers are investigating treatments for cancer that would infect the body with viruses lethal only to tumor cells. HUMAN SPACEFLIGHT 76 China’s Great Leap Upward 52 Robot walks using BY JAMES OBERG artificial muscles How China hopes to become the newest space superpower. ECONOMICS 84 The Economics of Child Labor BY KAUSHIK BASU Campaigns against child labor work better when they combine the long arm of the law with the invisible hand of the marketplace. www.sciam.com SCIENTIFIC AMERICAN 5 COPYRIGHT 2003 SCIENTIFIC AMERICAN, INC. departmentsSCIENTIFIC AMERICAN Volume 289 Number 4 8SA Perspectives Biotechnology even Europe can love. 10 How to Contact Us 10 On the Web 101 103 12 Letters 18 50, 100 & 150 Years Ago 42 Staking Claims 20 News Scan If the patent office needs a good, sharp kick, ■ Gaps in defending food against terrorism. this tinkerer can provide it. ■ Sexuality research ducks a conservative budget ax. ■ The race to find the superconductivity state. 44 Insights ■ Play it again: Treating musicians’ repetitive stress. Pekka Haavisto of the United Nations worries ■ Mapping the earth’s gravity. about the environmental impact of Gulf War II. ■ Flaws in studies of hormone replacement therapy? 92 Working Knowledge ■ By the Numbers: Interracial marriages. Smart fabrics for smart athletes. ■ Data Points: Fast-cracking crust. 94 Technicalities 38 Innovations The world’s largest video arcade could fit A serendipitous discovery could provide engineers in your living room. with a dream material: inexpensive titanium. 98 Reviews Small Things Considered explores the trade-offs 44 that make all designs imperfect. Pekka Haavisto columns 43 Skeptic BY MICHAEL SHERMER One hundred and six billion arguments against immortality. 101Puzzling Adventures BY DENNIS E. SHASHA Strategic bullying. 102 Anti Gravity BY STEVE MIRSKY Later, ’gator. 103Ask the Experts What causes insomnia? Why is the sky blue? 104Fuzzy Logic BY ROZ CHAST Cover image by Kenn Brown; SRI International (preceding page); Kate Brooks (left) Scientific American (ISSN 0036-8733), published monthly by Scientific American, Inc., 415 Madison Avenue, New York, N.Y. 10017-1111. Copyright © 2003 by Scientific American, Inc. All rights reserved. No part of this issue may be reproduced by any mechanical, photographic or electronic process, or in the form of a phonographic recording, nor may it be stored in a retrieval system, transmitted or otherwise copied for public or private use without written permission of the publisher. Periodicals postage paid at New York, N.Y., and at additional mailing offices. Canada Post International Publications Mail (Canadian Distribution) Sales Agreement No. 242764. Canadian BN No. 127387652RT; QST No. Q1015332537. Subscription rates: one year $34.97, Canada $49 USD, International $55 USD. Postmaster: Send address changes to Scientific American, Box 3187, Harlan, Iowa 51537. Reprints available: write Reprint Department, Scientific American, Inc., 415 Madison Avenue, New York, N.Y. 10017-1111; (212) 451-8877; fax: (212) 355-0408 or send e-mail to [email protected] Subscription inquiries: U.S. and Canada (800) 333-1199; other (515) 247-7631. Printed in U.S.A. 6 SCIENTIFIC AMERICAN OCTOBER 2003 COPYRIGHT 2003 SCIENTIFIC AMERICAN, INC. SA Perspectives Biotech’s Clean Slate When President George W. Bush scolded Europe last used to produce goods throughout history. Today’s June for resisting genetically modified crops, he was manufacturers can tweak cells in unprecedented ways, acting out his part in what has become one of the most however. The technology’s proponents argue that life- boring controversies in biotechnology. The U.S. always science solutions can lower production costs, create plays rah-rah cheerleader to Europe’s pouty bench- jobs, conserve resources and reduce pollution, to boot. warmer. Much of the public on both sides of the At- McKinsey and Company has projected that by lantic continues to reject transgenic food despite science 2010, between 10 and 20 percent of all chemical pro- and industry arguments about its benefits. Findings duction might involve biotechnology (up from rough- that point to risks from transgenic organisms are ly 5 percent now), reflecting about $280 billion in sales waved away as manageable by value. Such growth would require favorable circum- biotech’s advocates; findings stances—not the least of which, of course, is the con- that reinforce biotech’s safety tinued avoidance of a backlash like that tormenting ge- never surmount the precaution- netic crop developers. How likely is that? ary principle (do nothing new Industrial biotech’s best ace in the hole is the pub- until its safety is perfectly as- lic’s casual confidence in it. No one seems to protest sured). The story hasn’t pro- when industrial chemicals or other nonfood products gressed in years. come from genetically modified sources, probably be- What a relief, then, to con- cause the organisms are cloistered inside facilities. sider an often overlooked seg- Still, growth in industrial biotech may require more ment of biotech that has so far exposure of altered organisms to the outside world. As VATS OF CELLS grown for escaped the fracas. Industrial the complexity of the modified organisms rises, so, too, industrial biotech suffer little biotechnology applies the life might ethical objections. In 2002, when Nexia Biotech- critical scrutiny. sciences to manufacturing—for nologies created goats that had spider silk proteins in instance, by using cells to syn- their milk, the ethics of passing genes between such dis- thesize materials or by substituting enzymes for caus- similar species bothered many animal welfarists. At a tic reagents. more mundane level, just as claims that agricultural Last April in Lyon, France, the World Life Sciences biotech can feed the starving in poor countries incite Forum (BioVision 2003) dedicated much of its pro- debate, the proposition that industrial biotech will help gram to the subject, which some European authorities in the developing world needs to engage criticisms that call “white biotechnology” to distinguish it from the not all biotechnologies are easily exportable. agricultural (“green”) and medical (“red”) varieties. It seems inevitable that eventually a conflict will Similarly, at the Biotechnology Industry Organization oblige the public to see similarities between white and Photo Researchers, Inc. in Washington, D.C., in June, it was sometimes called green biotech. When that happens, perhaps this new / SPL the “third wave of biotechnology.” wave of biotech will suffer. Or perhaps—here’s a wild The sobriquets may be new, but the essence of in- thought—good experiences with industrial biotech will dustrial biotechnology is as old as bread and beer. reassure the public over its fears of genetically modi- Yeasts, molds and other microorganisms have been fied crops. Maybe the biotech impasse will budge yet. JAMES HOLMES/ THE EDITORS [email protected] 8 SCIENTIFIC AMERICAN OCTOBER 2003 COPYRIGHT 2003 SCIENTIFIC AMERICAN, INC. 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