Scientific American 04 2010 (journal magazine; April 2010)

88 Pages·2010·15.42 MB·English

by  Mariette DiChristina

CONTENTS FEATURES ■
SCIENTIFIC AMERICAN April 2010 ■ Volume 302 Number 4
SPECIAL REPORT: SUSTAINABILITY
5 3 LLIIVVIINNGG OONN AA NNEEWW EEAARRTTHH
5544 BBoouunnddaarriieess ffoorr aa HHeeaalltthhyy PPllaanneett
By Jonathan Foley
Scientists have begun to quantify red-alert levels for environmental problems.
58 Solutions to Environmental Threats
Experts spell out the actions that should be most effective.
61 Breaking the Growth Habit
By Bill McKibben
An exclusive excerpt from a provocative book says economic growth must stop.
66 Bill McKibben, Challenged
By Mark Fischetti
Is zero growth really necessary? McKibben answers questions about his stance. 61
ASTRONOMY
36 Eight Wonders of
44
the Solar System 36
By Edward Bell,
illustrations by Ron Miller
Tour some of the most breathtaking views that
await intrepid explorers of our solar system.
NEUROSCIENCE
44 Faulty Circuits
By Thomas R. Insel
Brain studies are revealing the malfunctioning
connections underlying mental illness.
MEDICINE
68 Regaining Balance 78
with Bionic Ears
By Charles C. Della Santina
Electronic implants in the inner ear may one day
72
help patients suffering from disabling unsteadiness.
TECHNOLOGY
72 The Rise of Instant
Wireless Networks
By Michelle Effros, Andrea Goldsmith
and Muriel Médard
Wireless networks that form on the fl y bring
communications to the most foreboding environments.
BIOLOGY ON THE COVER
78 The Hidden Life of Truffles
How can we sustain life on a planet undergoing
By James M. Trappe and Andrew W. Claridge many profound changes simultaneously?
Not just for gourmands, truffl es play essential roles Find an array of proposals in this issue.
in the health of ecosystems. Photoillustration by Aaron Goodman.
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CONTENTS DEPARTMENTS ■
6 From the Editor
8 Letters
12 50, 100 & 150 Years Ago
12
14 News Scan
20
TECHNOLOGY
■ Google’s muscle: worrisome or wondrous?
■ NASA loses a little mobile Spirit. 14
RESEARCH & DISCOVERY
■ Math problems solved by a Web community.
■ When humans almost went extinct.
■ New evidence that mammals fl oated to Madagascar.
ENERGY & ENVIRONMENT

■ Engine-ready diesel fuel from bacteria.
■ High sea levels even during an ice age.
MEDICINE & HEALTH
■ Should younger, healthy people take statins?
■ Sound can affect what you smell.
35A Critical Mass
30 Perspectives
By Lawrence M. Krauss
By the Editors Sometimes the pursuit of a great discovery
Federal agencies need more power to ban chemicals. is its own reward.
32 Sustainable Developments 86 Recommended
By Jeffrey D. Sachs
Imperiled species. Sleeping sickness. Human ancestors.
Combined with community involvement, information
and communications technologies can save lives. 88 Anti Gravity
34 Skeptic By Steve Mirsky
Cheetos, clones and chimp
By Michael Shermer
cinematographers .
How the brain produces the sense of someone
GO TO
present when no one is there.
.COM
34 RTheev ofi lrustt iionnnoizviantgio Enn seurmgmy iitn o tf hthee U U.S.S.. Department of Energy’s © 2010
AEndevragnyc Seedc Rreetsaerayr cShte Pvreonj eCchtsu Ahgaes nccayll esdo u“gthhet tnoe xint iitniadtues wtrihaal t GY AND NIZATION,
OA
rreevvoolluuttiioonn iinn cclleeaann eenneerrggyy tteecchhnnoollooggiieess..”” AN TECHNOLUSTRIES ORG
35A More at www.Scientifi cAmerican.com/apr2010 COURTESY OF CLESUSTAINABLE IND
Scientifi c American (ISSN 0036-8733), Volume 302, Number 4, April 2010, published monthly by Nature Publishing Group, a trading name of Nature America, Inc., 75 Varick Street,
9th Floor, New York, N.Y. 10013-1917. Copyright © 2010 by Scientifi c American, Inc. All rights reserved. No part of this issue may be reproduced or transmitted in any form or
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from the editor ■
Small World
Board of advisers
LesLie C. AieLLo john p. mooRe
President, Wenner-Gren Professor of Microbiology
Foundation for and Immunology, Weill Medical
Anthropological Research College of Cornell University
RogeR BinghAm m. gRAngeR moRgAn
Professor, Center for Brain Professor and Head of
and Cognition, University Engineering and Public Policy,
of California, San Diego Carnegie Mellon University As I type this column, several only human after all, are also imperfect.
g. steven BuRRiLL migueL niCoLeLis recent storms are weighing But the advancement of science involves
CEO, Burrill & Company Co-director, Center for
ARthuR CApLAn Neuroengineering, on my mind. Winter snow- a preponderance of evidence. Thousands
Emanuel and Robert Hart Duke University falls around the country have of studies, conducted over decades, indi-
Professor of Bioethics, mARtin nowAK
University of Pennsylvania Director, Program for sparked questions about cli- cate that humanity’s thumbprints are
seAn CARRoLL Evolutionary Dynamics,
mate change yet again. Skeptics ask, How molding the planet. Readers of Scientific
Senior Research Associate, Harvard University
Department of Physics, RoBeRt pALAzzo can warming be happening if we’re get- American first learned that excess carbon
Caltech Provost and Professor
geoRge m. ChuRCh of Biology, Rensselaer ting big snows? As if we could determine dioxide could detrimentally affect climate
Director, Center for Polytechnic Institute the world’s condition during a single sea- in a feature article that ran back in 1959—
Computational Genetics, viLAyAnuR s.
Harvard Medical School RAmAChAnDRAn son. In fact, one symptom of a changing that’s right, 50 years ago. Today science is
RitA CoLweLL Director, Center for Brain
climate could be more varied or more ex- still grappling with uncertainties over the
Distinguished Professor, and Cognition, University
University of Maryland of California, San Diego treme weather—but a couple of heavy degree of human influence, but the work
College Park and Johns LisA RAnDALL
Hopkins Bloomberg School Professor of Physics, snows wouldn’t prove that either. January of thousands of researchers before and
of Public Health Harvard University was slightly warmer in the U.S. than aver- since that 1959 article shows that
DRew enDy mARtin Rees
Professor of Bioengineering, Professor of Cosmology age, in any case. it does exist.
Stanford University and Astrophysics,
eD FeLten University of Cambridge Another storm surrounds “Climate- In this issue, a special
Director, Center for Information john RegAnoLD gate.” More than 1,000 private e-mails report starting on page
Technology Policy, Regents Professor of Soil
Princeton University Science, Washington were stolen from the University of East 53 reveals how we have
miChAeL s. gAzzAnigA State University Anglia’s Climatic Research Unit and pub- fundamentally altered
Director, Sage Center for jeFFRey D. sAChs
the Study of Mind, University Director, The Earth Institute, licly released last November. Climate Earth—its climate, its
of California, Santa Barbara Columbia University
DAviD gRoss eugenie sCott doubters have asserted that the e-mails resources, its ecosys-
Frederick W. Gluck Professor of Executive Director, National prove that science surrounding global cli- tems—and offers ideas
Theoretical Physics, University Center for Science Education
of California, Santa Barbara teRRy sejnowsKi mate change is not settled and that the for what we can do about
(Nobel Prize in Physics, 2004)
Lene vesteRgAARD hAu Professor and Laboratory data in favor of it were misrepresented. it. “Boundaries for a Healthy
Head of Computational
Mallinckrodt Professor of Neurobiology Laboratory, Disturbingly, a few mistakes were also Planet,” by atmospheric scientist Jona-
Physics and of Applied Physics, Salk Institute for
Harvard University Biological Studies recently uncovered in the second of the than Foley, explains the safe thresholds
DAnny hiLLis miChAeL snyDeR climate research reports produced in 2007 for environmental processes that pro-
Co-chairman, Applied Minds Professor of Genetics,
DAnieL m. KAmmen Stanford University School by the Intergovernmental Panel on Cli- foundly affect sustainability. Then, “Solu-
Director, Renewable and of Medicine mate Change; the second report examines tions to Environmental Threats” provides
Appropriate Energy Laboratory, miChAeL e. weBBeR
University of California, Associate Director, Center the current effects of climate change and a set of experts’ takes on approaches we
Berkeley for International Energy
vinoD KhosLA & Environmental Policy, forecasts future effects. (No errors have could employ to keep those processes with-
Founder, Khosla Ventures University of Texas at Austin been found in the first, and most often in limits. Next, in “Breaking the Growth
ChRistoF KoCh steven weinBeRg
Lois and Victor Troendle Director, Theory Research quoted, report, which says that the evi- Habit,” Middlebury College scholar in res-
PBreohfaevsisoorra ol fB Cioologgniyt,i vCea latnedch GUnroivuepr,s Diteyp oafr Ttemxeanst a otf A Puhsytsinic s, dence is incontrovertible that human ac- idence Bill McKibben contends that, to
LAwRenCe m. KRAuss (Nobel Prize in Physics, 1979) tivity is causing the atmosphere to warm survive, society must end its addiction to
Director, Origins Initiative, geoRge m. whitesiDes
Arizona State University Professor of Chemistry and and the seas to rise.) economic growth in favor of smart main-
moRten L. KRingeLBACh Chemical Biology, Last, in December, the much anticipat- tenance of wealth and resources. Skepti-
Director, Hedonia: TrygFonden Harvard University
Research Group, University of nAthAn woLFe ed climate summit in Copenhagen failed to cal? Staff editor Mark Fischetti questions
Oxford and University of Aarhus Director, Global Viral
sPECcrotoorefnneveoslemsl onUicr n sKoi avfy enALrdpse piMtlyiaenda gement, FRVVoea. rnnjettcAuaargmeset ePPinaosgri n twIntn oeVitroei,a n Lttisuvreee y , jR. pgUrr.eoSe.d nluehcgoeisu lasa etsi ioegmnn ioifisnsc itaohnnotss ;ae agftrr oetenhmtes eshnaatms tseot a tcilmluerdeb,. slteiuoncnghse ados.r”s en Wrottih,o ewntseh iehnro “ypBoeu iyl loa Mug rwceKei liwlb fibitnehdn t,th hCee h neaoxl--- asa (Earth)
RDPLrAaoovwBfiedeRs HRseo.tn rK ,Cs oMe.c .hLLI .AITen.nsstsgitieugRte PAPQarunoratftnenosteusnroms rz Noefai LQnoiunpaghnyteusRimcs O, ptics, Eofa trAhthes s Dwe aeeyv m etnhatirssk? A Itpth risei l t,4r wu0eht hath ta aantr ena tiwvmeeo rtsosap mrhyea rkoicef cinhfaonrgmea, atinvde tahned s tpheocuiaglh ste-cptrioovno aksi an gw. h ole■, DiChristina); n
PeCRreocnfiele sassnotdr ,Ij dH.a am rGvoraenredin zL aw School QUjonuianvneAtrutsmihty AI nonff o VzrimietnatntiRaoAn,i n science is complex and climate models are mariette diChristina an hill (
Distinguished Professor. M.I.T. Professor, Harvard Law School imperfect. Clearly, scientists, who are editor in chief eth
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LEttErS ■
[email protected]
®
Hydrothermal Vents Ocean Policy Ancient Greeks
■ ■
Established 1845
EDITOR IN CHIEF: Mariette DiChristina
MANAGING EDITOR: Ricki L. Rusting
CHIEF NEWS EDITOR: Philip M. Yam
SENIOR WRITER: Gary Stix “We need to find the ‘Ardi’
EDITORS: Davide Castelvecchi,
of the Antikythera.”
Graham P. Collins, Mark Fischetti,
Steve Mirsky, Michael Moyer, George Musser, —Lowndes Whatley ROSWELL, GA.
Christine Soares, Kate Wong
CONTRIBUTING EDITORS: Mark Alpert,
Steven Ashley, Stuart F. Brown, W. Wayt Gibbs,
Marguerite Holloway, Christie Nicholson,
Michelle Press, John Rennie, Michael Shermer,
Sarah Simpson DECEMBER 2009
ASSOCIATE EDITORS, ONLINE: David Biello, ■ Lost Nucleotides which relies on the chemistry of much simpler organ-
Larry Greenemeier Although Alexander S. Bradley’s arti- ic compounds. Reconciliation of the geochemical re-
NEWS REpORTER, ONLINE: John Matson
cle “Expanding the Limits of Life” pro- quirements for the origins of RNA and metabolism
ART DIRECTOR, ONLINE: Ryan Reid
vides a fascinating account of the discov- has remained elusive—we do not yet have a theory
ery of microbes in a previously unknown for the origin of life. Until we do, sites like Lost City
ART DIRECTOR: Edward Bell
kind of hydrothermal vent ecosystem on provide critical constraints on the range of potential
ASSISTANT ART DIRECTOR: Jen Christiansen
pHOTOGRApHY EDITOR: Monica Bradley the seafloor, it does not substantiate his prebiotic environments on Earth and beyond.
claim that the findings hint that life may
have originated in an environment like the ■ Zoned In
COpY DIRECTOR: Maria-Christina Keller
Lost City hydrothermal vent. Having long argued that tradable rights
Bradley suggests that Lost City produc- and subleasing options are critical compo-
EDITORIAL ADMINISTRATOR: Avonelle Wing
es “small organic acids such as formate and nents of ocean zoning, I was encouraged
SENIOR SECRETARY: Maya Harty
acetate” and that similar vents might have to see these ideas displayed so prominent-
produced “simple organic acids” and “even ly in “Zoning for Oceans” [Perspectives].
COpY AND pRODUCTION, NATURE pUBLISHING GROUp:
SENIOR COpY EDITOR, NpG: Daniel C. Schlenoff more complex fatty acids” or “at least sim- The ability to trade and negotiate encour-
COpY EDITOR, NpG: Michael Battaglia ple organic compounds.” Such statements ages participation in what otherwise could
EDITORIAL ASSISTANT, NpG: Ann Chin do not begin to address the conditions and be a very rigid top-down management ap-
MANAGING pRODUCTION EDITOR, NpG:
processes that led to the assembly of the proach. It can also encourage more effi-
Richard Hunt
SENIOR pRODUCTION EDITOR, NpG: Michelle Wright nucleotides—adenine, guanine, cytosine, cient use of fish and other resources that
thymine and uracil—nor do the statements are prone to shift over space and time, re-
indicate that the materials necessary to ducing the necessity during the design
pRODUCTION MANAGER: Christina Hippeli
ADVERTISING pRODUCTION MANAGER: form the nucleotides might be present in phase of trying to match the ecosystem
Carl Cherebin hydrothermal vents. scale with the policy scale—nearly impos-
pREpRESS AND QUALITY MANAGER: Studies of life in hydrothermal vents sible given the myriad socioeconomic and
Silvia De Santis
and of the chemistry of hydrothermal ecological considerations. For more de-
CUSTOM pUBLISHING MANAGER:
Madelyn Keyes-Milch vents have provided no information about tails, please visit Resources for the Future
the evolution of RNA and DNA and of (www.rff.org/oceanzoning).
their nucleotides from inorganic and sim- James N. Sanchirico
Letters to the Editor
ple organic molecules. Department of Environmental Science and Policy
Scientific American
Richard A. Ely University of California, Davis
75 Varick Street, 9th Floor,
New York, NY 10013-1917 Dallas, Tex.
or [email protected] ■ The Incredible Mechanism
Letters may be edited for length and clarity. BRADLEY REPLIES: The reader calls attention to a After the marvel, shock and awe of the
We regret that we cannot answer each one. long-standing question in origins of life research. Antikythera mechanism described by
Post a comment on any article instantly at Scientists widely agree that RNA preceded DNA as Tony Freeth in “Decoding an Ancient
www.ScientificAmerican.com/
sciammag the molecule of heredity. But it is not clear whether Computer,” there are more questions.
RNA preceded or followed the origin of metabolism, This machine was obviously not a one-off
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letterS ■
or even the first of its kind; there had to be editor grahaM P. coLLins rePLies: The ques-
predecessors. Otherwise it would be as if tion reminds me of the one time in my life I spoke to
®
someone 1,000 years from now found an Richard Feynman. I was in 7th form in high school,
Infiniti Q45 buried in mud and said we and after Feynman gave a public lecture at Auckland
Established 1845
must have got tired of walking. We need University I went up and asked him: If nothing can
to find the “Ardi” of the Antikythera. get out of a black hole, how could the gravitons that
Then there is the manufacturing. Mak- create its gravitational field get out? The answer is preSiDent: Steven Inchcoombe
Vice preSiDent, operAtionS AnD
ing machine gears requires precision tools that the gravitons are virtual particles, which can
ADminiStrAtion: Frances Newburg
and considerable expertise. These were not move faster than the speed of light and thus can es-
Rolex watches, but they had to have a high cape from the black hole. mAnAging Director, conSumer mArketing:
level of precision to operate so many gears Christian Dorbandt
in the drive train. Below ■ War or Peace ASSociAte Director, conSumer mArketing:
Anne Marie O’Keefe
a certain level of preci- I was disappointed and dismayed by
Senior mArketing mAnAger/retention:
sion the inefficiency of Lawrence M. Krauss’s “War Is Peace” Catherine Bussey
the gearing would [Critical Mass]. I agree with his political Senior mArketing mAnAger/AcquiSition:
Patricia Elliott
positions, but the way he presented them
was shallow, unthoughtful and insulting
AntikYtHerA Vice preSiDent AnD puBLiSHer:
mechanism to people who have genuinely held posi- Bruce Brandfon
revealed tions that differ from his own. Vice preSiDent, mArketing AnD
un expected Krauss’s piece makes the magazine look SALeS DeVeLopment: Michael Voss
Director, gLoBAL meDiA SoLutionS:
so phistication like a liberal blowhard—especially because Jeremy A. Abbate
in ancient-world Krauss provides no thoughtful policy anal- mAnAger, integrAteD meDiA SALeS: Stan Schmidt
technology. ysis, no new insights into the science of SALeS DeVeLopment mAnAger: David Tirpack
promotion mAnAger: Diane Schube
health care or politics, and it treats anyone
mArketing reSeArcH Director: Rick Simone
make the whole thing with whom he disagrees with great disre- SALeS repreSentAtiVeS: Jeffrey Crennan,
inoperable. To make a spect. (“Zombielike protesters”? No—ac- Chantel Arroyo
large, thin gear on a shaft tive citizens who disagree with him.)
with very small gear teeth David G. Haskell Vice preSiDent, finAnce AnD
BuSineSS DeVeLopment: Michael Florek
mesh without wobbling, run in both di- department of biology BuSineSS mAnAger: Marie Maher
rections, and control dials and pointers university of the south
several gear sets away without much play sewanee, tenn. Director, AnciLLArY proDuctS: Diane McGarvey
or lash requires a level of sophistication
in metallurgy, machine design and preci- Krauss rePLies: I appreciate the concerns ex- How to Contact Us
sion machining on a level with the con- pressed by Haskell, but I think he misinterpreted the
cept, design and purpose of this incredible point. My piece was not about health care or climate SuBScriptionS
For new subscriptions, renewals, gifts, payments,
mechanism. change per se. It was about disinformation replacing
and changes of address: U.S. and Canada,
Lowndes Whatley information in the media regarding such issues. It 800-333-1199; outside North America, 515-248-7684
roswell, ga. was in this regard that I expressed contempt for both or www.ScientificAmerican.com
right-wing fanatic radio hosts (if I knew of any really
■ Exit Strategy left-wing fanatic radio hosts I might respond equally reprintS
In “Portrait of a Black Hole,” Avery E. negatively) and ex-politicians who fabricate claims To order reprints of articles: Reprint Department,
Scientific American, 75 Varick Street, 9th Floor,
Broderick and Abraham Loeb explain about “death panels.” Thus, it is not their views that
New York, NY 10013-1917; fax: [phone];
that inside the event horizon of a black I tried to express contempt for. It is their lies and dis- [email protected]
hole everything moves toward the singu- tortion. No doubt I could have been more polite, but
larity. In particular, any virtual gravitons I think it is an issue we need to be upset about.
einmsiitdtee dt hbayt tshien sgiunlgaurliatyr.i tTy hweirlel fboer ter,a tphpeerde errAtA in “expanding the Limits of Life,” alexan- FDpoeerrp pameritrSmmSeisinostino, SnSc tioe nctoipfiyc oArm reeuriscea nm, a7t5e rViaalr:i cPke rSmtriesesito, n9st h ny freeth
could be no gravitation field outside the der s. bradley writes that “up to one third of the mi- Floor, New York, NY 10013-1917; [email protected]; d to
singularity, and the space around the sin- crobes at Lost city are methanogens belonging to the wPlewawse.S acllioewnt itfihcreAem toe rsiicxa wn.eceokms /fpoer rpmroiscseisosninsg. . on an
gularity must be flat. But in that case, family Methanosarcinales.” that should be the order was
ntoontsh firnogm w foreuelldy phrionpdaegr atthine gv.i Irst tuhaelr ge raa svoi-- Metihna “nsoestatirncign abloeusn, ndoatr itehse” f[anmewilys. scan], david biel- AwDwVwe.rStciieSnitnifigc American.com has electronic n by griff
o
lution to this conundrum? lo wrote that one cubic kilometer was equal to “about contact information for sales representatives cti
Moshe Rozenblit 264 trillion gallons.” the correct conversion is 264 aonf Sdc iine nottihfiecr Acomuenrtirciaens .in all regions of the U.S. nstru
o
Jersey city, n.J. billion gallons. rec
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Scientific AmericAn April 2010