Scientific American (December 2017)

102 Pages·2017·17.99 MB·English

by  Scientific American

PLUTO REVEALED I FEEL YOUR PAIN CLOUDS AND CLIMATE
Inside the New Horizons mission The new science of empathy Will they make things better or worse?
PAGE 40 PAGE 58 PAGE 72
World-changing ideas that are poised to transform society

December 2017
VOLUME 317, NUMBER 6
0408
PSYCHOLOGY
SPECIAL REPORT 58 I Feel Your Pain
28 TOP 10 A new understanding of empathy
might help us harness the emotion—
EMERGING
just when we need it the most.
TECHNOLOGIES By Lydia Denworth
2017
OF
CONSERVATION
A collaboration between 64 Beetle Resurrection
Scientific American a nd Oil companies want the American
the World Economic Forum. burying beetle off the endangered
species list. Scientists say comeback
claims are wildly exaggerated.
PLANETARY SCIENCE
By Hannah Nordhaus
40 Pluto Revealed
nasa’s New Horizons changed CLIMATE
everything we thought we knew 72 The Cloud Conundrum
about this distant planet. Will changing cloud cover acceler-
By S. Alan Stern ate global warming or slow it
down? By Kate Marvel
GENETICS ON THe cOVer
MYTAGE Alamy 48 ECthnoeug Glidna eGleárepinaneggto iScs? a ve 78 AHCRhoCawHnA CgEeaOdpL OttihGveeY  sW orld TFbhoyi rsSu csmipe’ensct Eiifiaxclp rAeemrptoe Nrritec,a tcwno oamnrkpd,i lthehidge h aWlnigdoh rptldsro 1Ed0cu oecmneodem r gic-
N-AR Invasive species are a problem. Stolen people were a driving force ing technologies with genuine momentum
NNIE GREE Isso gluetnioenti?c Bmya Sntieppuhlaenti oSn. H thaell Biny t Chae tehveorliuntei oMn.  oCfa mmoedroenrn society. Iaamnndda gtehece ob npyoo Mmteaincrt kiba eRl ntooes fisct.rse.ate significant social
A
December 2017, ScientificAmerican.com 1
© 2017 Scientific American
4 From the Editor
5 Letters
7 Science Agenda
Protecting the warming Arctic from economic and military
exploitation is imperative. By the Editors
10 Forum
The demise of DACA harms everyone’s health.
By Sahand Ghodrati
12 Advances
Plate tectonics get a new birth date. How smoke from
wildfires can spoil wine. Lizards compensate for losing
22 their tail. Damage from solar storms could cost trillions.
25 The Science of Health
More worries about the teen brain on marijuana.
By Claudia Wallis
26 TechnoFiles
How shareable should digital subscriptions be?
By David Pogue
86 Recommended
Enrico Fermi and the nuclear age. Birders’ quest to count
as many species as possible. The Vienna Circle’s influence
on science philosophy, post-WWI. B y Andrea Gawrylewski
88 Skeptic
Can we agree to outlaw war—again? B y Michael Shermer
25
90 Anti Gravity
Burying nuts requires squirrel smarts. By Steve Mirsky
92 50, 100 & 150 Years Ago
94 Graphic Science
Looking for alien worlds closest to our own. B y Lee Billings
and Nadieh Bremer
ON THE WEB
Do-It-Yourself CRISPR
Scientific American e xamines how a new and easy-to-use
D.I.Y. gene-editing tool will change science and society.
Go to www.ScientificAmerican.com/dec2017/crispr
88
Scientific American (ISSN 0036-8733), Volume 317, Number 6, December 2017, published monthly by Scientific American, a division of Nature America, Inc., 1 New York Plaza, Suite 4500, New York, N.Y. 10004-1562. Periodicals postage
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Copyright © 2017 by Scientific American, a division of Nature America, Inc. All rights reserved.
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2 Scientific American, December 2017
© 2017 Scientific American

FROM
THE EDITOR
Mariette DiChristina is editor in chief of Scientific American.
Follow her on Twitter @mdichristina
Let’s Science
math Bernard S. Meyerson, chief innovation officer of IBM. With
the help of knowledgeable council members, we produced ter-
That
rific lists for two years.
After our council term ended, our Forum lead, Rigas Hadzila-
cos, asked me if Scientific American might like to continue to help
As an editor, I’ve never been a big fan of turning nouns into develop the Top 10 Emerging Technologies list. He proposed that
verbs when perfectly good options already exist. But I’d be hap- we could tap the knowledge of members of the Forum’s Expert
py to see us use “science” that way. It’s a powerful, evidence- Network and Global Future Councils; we also planned to reach
based process of conducting experiments, out to the ever savvy Scientific American
gathering data and performing analysis board of advisers and other specialists who
on the results. It’s at once a methodical keenly observe developing innovations.
set of practices and a tool that inspires Not least, Meyerson also smilingly told me
hope for a brighter future by advancing he’d enjoy the chance to work for m e this
discovery and innovation. time around. How could I resist an oppor-
That’s why our cover story, “Top 10 tunity like that? I’m grateful to all who gen-
Emerging Technologies of 2017,” has a spe- erously helped to shape this collaboration
cial resonance for me. It’s about world- and to the editorial team members who
changing ideas coming out of the labs that have now brought it to you in this edition.
are poised to help us lead better, healthier Elsewhere in our pages, you’ll find lots
lives. Scientific American produced the of other ways science is making a differ-
section in collaboration with the World ence: changing everything we thought we
Economic Forum. The Forum annually knew about a “former” planet (“Pluto Re -
brings together business and policy leaders—and, increasingly, vealed,” page 40); helping us understand how the tragic history
scientists and their research—to discuss ways we can work of stolen people has forged modern society (“How Captives
together to tackle the world’s greatest challenges. Turn to page 28. Changed the World,” page 78); illuminating the true population
The partnership that led to this special report began three health of American burying beetles (“Beetle Resurrection,” page
years ago. I was invited to serve as vice chair of one of the 64); and exploring the implications of possibly using new gene-
Forum’s past Global Agenda Councils, focused on identifying editing techniques to preserve ecosystems in the Galápagos
emerging technologies. Our chair was the irrepressible poly- (p age 48) . Have a question? Let’s science that.
BOARD OF ADVISERS
Leslie C. Aiello Kaigham J. Gabriel Christof Koch Martin A. Nowak Terry Sejnowski
President, Wenner-Gren Foundation President and Chief Executive Officer, President and CSO, Director, Program for Evolutionary Professor and Laboratory Head
for Anthropological Research Charles Stark Draper Laboratory Allen Institute for Brain Science Dynamics, and Professor of Biology and of Computational Neurobiology
Roger Bingham Harold “Skip” Garner Lawrence M. Krauss of Mathematics, Harvard University Laboratory, Salk Institute for
TChoe- FSocuienndceer Nanedtw Doirrek ctor, Executive Director and Professor, Director, Origins Initiative, Robert E. Palazzo Biological Studies
Arthur Caplan Primary Care Research Network Arizona State University Dean, University of Alabama at Michael Shermer
Director, Division of Medical Ethics, and Center for Bioinformatics and Morten L. Kringelbach Birmingham College of Arts and Sciences Publisher, Skeptic magazine
Department of Population Health, Genetics, Edward Via College Associate Professor and Senior Carolyn Porco Michael Snyder
NYU Langone Medical Center of Osteopathic Medicine Research Fellow, The Queen’s College, Professor of Genetics, Stanford
VGieCnohtoriegnf e IGn Mt.e C.r nCeerhtf u E rvcahn g elist, Google MDoicfi rhMeacientodl rS, ,U .S Gnaigaveez rCzsaeitnnyti eogrfa Cf o arl itfhoer nSitau, d y StUPernvoiefvenes rsKsoiytryl eo of fA Opxpfloierdd Economics and TSLepeaaamdcee, raS, ncCdiae Dsnsciirene iI cnImtsotari,tg uCintIeCg L SOcPieSn,c e MUCiconh-ivdaeierrels cEitt.yo WSr,c Cehlboeboalne o rEf nMeregdyic Iinnceu bator,
DGeirneecttiocrs, ,C Heanrtvear rfdo rM Ceodmicpaul Stacthioonoal l Santa Barbara RoMbaenratg Se.m Leanntg, Ceor rnell University ViDlaiyreacntourr, CS.e Rntaemr faocr hBraanind raannd C ognition, Danedp Aarstsmoceinatt eo fP Mroefecshsaonri,c al Engineering,
Rita Colwell David J. Gross David H. Koch Institute Professor, University of California, San Diego University of Texas at Austin
Distinguished University Professor, Professor of Physics and Permanent
Department of Chemical Lisa Randall Steven Weinberg
University of Maryland College Park Member, Kavli Institute for Theoretical
and Johns Hopkins Bloomberg School Physics,University of California, Santa Engineering, M.I.T. Professor of Physics, Director, Theory Research Group,
of Public Health Barbara (Nobel Prize in Physics, 2004) Lawrence Lessig Harvard University Department of Physics,
RDiRFrceoihcwuhana rEddrned Dr dD ayaan ww d kkBiionnass rF do Cuhnadiartmioann , LeMonf aeAl lpVinpeclsiketrdeo rPdgth aPyasroircdfse ,sH Hsaoaurr vo af rPdh Uysnicivse arnsidty JoIPPhmrrnoom ffPeeu.ss nMssooolrroo, ooHgfry aMe,r W v icaerroidllb LMioalewod gSicyca hal no do l MAoafsr Cttrioonsn mRoemoeloesrg Ry oaynadl Aanstdr oPprohfyessiscosr, Ge(UPNornoorifvbgeeeesrls s MPoitrry i.oz oWef f C iTnhhe iPetxmheayssi ssiaditctre sAys, ua1 9snt7di9n )
Professor of Bioengineering, Danny Hillis College of Cornell University Institute of Astronomy, University Chemical Biology, Harvard University
Stanford University Co-chairman, Applied Minds, LLC M. Granger Morgan of Cambridge Anton Zeilinger
Edward W. Felten Daniel M. Kammen Hamerschlag University Professor Jeffrey D. Sachs Professor of Quantum Optics,
JoTDneiacrehthcntaoonlro, FgCoye lPneotyeli r c fyo, rP Irninfocremtoant iUonn iversity Cofl aEsnse orfg 1y9, 3E5n eDrigsyti nagnud iRsheesdo uPrrcoefse s sor ECnagrnineegeieri nMge allnodn PUunbivlice rPsoitlyic y, DCoirleucmtobri,a T Uhnei Evearrsthit yIn stitute, IQnufoarnmtuamtio Nna, Unonpivheyrssiictys, oQf uVaienntunma
Executive Director and Group, and Director, Renewable and Miguel Nicolelis Eugenie C. Scott Jonathan Zittrain
William R. and Gretchen B. Kimball Chair, Appropriate Energy Laboratory, Co-director, Center for Chair, Advisory Council, Professor of Law and of Computer
California Academy of Sciences University of California, Berkeley Neuroengineering, Duke University National Center for Science Education Science, Harvard University
Illustration by Eric Petersen (eyepiece),
4 Scientific American, December 2017 Illustration by Nick Higgins (DiChristina)
© 2017 Scientific American
LETTERS
[email protected]
“ Before trying to tion and has developed a campaign to re-
duce it by 50 percent by 2030.
increase crop yields,
Olga Syraya D üsseldorf, Germany
we must find ways to
Broadfoot’s article largely ignores an im-
reduce inefficiencies
portant consequence of crop yield increas-
in our food produc- es: they can depress market prices for the
crops. Unless they provide more income
tion and distribution.”
despite falling prices, higher yields may do
olga syraya d üsseldorf, germany the farmers more harm than good.
In addition, although Broadfoot con-
cludes with a brief mention of the prob-
and when it is not. If one side adopts it, it lems involved in getting food into the
is in the interest of the other side to do so hands of the starving, that observation
to prevent a nuclear Armageddon, at least conceals an important point: if we stopped
given that both sides have second-strike putting our crops into the bellies of cattle
capability (as the U.S. and Russia do). and ethanol fermenters and the hands of
For a state like North Korea, which dictators, we could probably feed the world
August 2017 does not have such capability, retaliation right now without having to increase
by the U.S. would almost certainly wipe yields, and doing so would also reduce
out its future capability and annihilate its pressure on the environment created by
NUCLEAR MATTERS leadership. So even though North Korea high-intensity agriculture. Sometimes hu-
In “Nuclear War Should Require a Second may not agree to NFU, it would be foolhar- man problems require human solutions.
Opinion” [Science Agenda], the editors ar- dy for it to seriously consider a first strike, Geoff Hart v ia e-mail
gue that the president of the U.S. should which translates into its implicit adoption.
not be the only person to decide on wheth- Steven J. Brams Professor of politics, MENTAL MONOLOGUE
er or not to cause worldwide havoc by or- New York University “Talking to Ourselves,” by Charles Ferny-
dering a nuclear launch and that “we need hough, discusses studies on the neural
to ensure at least some deliberation.” CROP TALK bases of people talking to themselves in
Alone or through informed advice and In “Building a Better Harvest,” Marla their mind. I wonder if any research has
widespread consent, threatened by ene- Broadfoot reports on efforts to utilize the been done to determine if such “inner
mies or not, an American president (or phytobiome—the web connecting crops speech” is still present in people suffering
any other president) should n ever h ave with environmental factors such as micro- from dementia or Alzheimer’s disease—or
the power to destroy the world. The U.S. bial communities—to avoid famines. I ap- if it is present but in a different form. My
has countless other ways to make adver- preciate that crop science aims to adopt a mother-in-law sat motionless for hours,
saries sorely regret threatening it. more holistic approach. But I am some- unable to speak to us, and I always won-
Stelios Bakalis T hessaloniki, Greece what perplexed by Broadfoot’s assertion dered if she still could speak to herself.
that yields must increase by 70 percent, as Sandra Robbins C arlsbad, Calif.
Your editorial’s recommendation introduc- concluded in a 2009 United Nations Food
es ambiguity. Would it be desirable for the and Agriculture Organization (FAO) dis- I would like to know if any of the brain
president to consult “high-ranking mem- cussion paper, to satisfy population growth pathways found in the research on self-
bers of Congress” after a first strike, or the and increasing meat consumption. talk could be similar to dreaming. It seems
imminence of one, when these members Before trying to increase crop yields, like dreaming might be an uncontrolled
might themselves be divided? And how we must find ways to reduce inefficiencies visual re-creation of the process.
many need to affirm? To minimize delay in our food production and distribution. Lanny Schroeder v ia e-mail
and the possibility of error, might not it be About a third of edible food is wasted glob-
better to require the secretary of defense ally, and the FAO found that 6.7 percent of FERNYHOUGH REPLIES: R egarding Rob -
or the national security advisor, or both, to global greenhouse gases comes from food bins’s question: Inner speech is difficult to
certify that there is unmistakable evidence waste. Further, a June 2010 report by the study. In the case of individuals with de-
that these weapons have been used? United Nations Environment Program mentia, the problem of obtaining reliable
What constitutes evidence would be urged a global shift toward a plant-based reports on inner experience is even more
clarified by a policy of “no first use” (NFU) diet to fight hunger, poverty and climate acute. It appears likely to me that inner
of nuclear weapons. NFU draws a bright change. And adoption of such a diet would speech will continue in people who, for rea-
line between when the use of such weap- make people healthier. China has already sons including dementia, don’t use much
ons is justified—in particular, to retaliate recognized the environmental and health spoken language. One possibility for inves-
against their first use by another country— threat posed by growing meat consump- tigating such speech in dementia would be
December 2017, ScientificAmerican.com 5
© 2017 Scientific American
LETTERS
[email protected]
ESTABLISHED 1845
EDITOR IN CHIEF AND SENIOR VICE PRESIDENT
Mariette DiChristina
to develop nonverbal measures, such as DIGITAL CONTENT MANAGER Curtis Brainard COPY DIRECTOR Maria-Christina Keller CREATIVE DIRECTOR Michael Mrak
pictorial representations of aspects of in- EDITORIAL
CHIEF FEATURES EDITOR Seth Fletcher CHIEF NEWS EDITOR Dean Visser CHIEF OPINION EDITOR Michael D. Lemonick
ner speech, that could be used with individ-
FEATURES
uals who express little external language. SENIOR EDITOR, SUSTAINABILITY Mark Fischetti SENIOR EDITOR, SPACE / PHYSICS Clara Moskowitz
SENIOR EDITOR, CHEMISTRY / POLICY / BIOLOGY Josh Fischman SENIOR EDITOR, TECHNOLOGY / MIND Jen Schwartz
In answer to Schroeder: Dreaming oc- SENIOR EDITOR, EVOLUTION / ECOLOGY Kate Wong
curs mainly (though not exclusively) dur- NEWS
SENIOR EDITOR, MIND / BRAIN Gary Stix ASSOCIATE EDITOR, BIOLOGY / MEDICINE Dina Fine Maron
ing the rapid eye movement (REM) sleep ASSOCIATE EDITOR, SPACE / PHYSICS Lee Billings ASSOCIATE EDITOR, SUSTAINABILITY Annie Sneed
stage, when activity in the brain’s cerebral ASSOCIATE EDITOR, TECHNOLOGY Larry Greenemeier ASSISTANT EDITOR, NEWS Tanya Lewis
DIGITAL CONTENT
cortex is similar to that observed when MANAGING MULTIMEDIA EDITOR Eliene Augenbraun ENGAGEMENT EDITOR Sunya Bhutta
people are awake. Methodologically, tying SENIOR EDITOR, MULTIMEDIA Steve Mirsky COLLECTIONS EDITOR Andrea Gawrylewski
particular dreams involving speech to ac- ART
ART DIRECTOR Jason Mischka SENIOR GRAPHICS EDITOR Jen Christiansen PHOTOGRAPHY EDITOR Monica Bradley ART DIRECTOR, ONLINE Ryan Reid
tivation in language and other pathways ASSISTANT PHOTO EDITOR Liz Tormes ASSISTANT GRAPHICS EDITOR Amanda Montañez
would be extremely hard. One way for- COPY AND PRODUCTION
ward might be through obtaining detailed SENIOR COPY EDITORS Michael Battaglia, Daniel C. Schlenoff         COPY EDITOR Aaron Shattuck
MANAGING PRODUCTION EDITOR Richard Hunt PREPRESS AND QUALITY MANAGER Silvia De Santis
self-reports on dreams by adapting exist-
DIGITAL
ing techniques of experience sampling. But SENIOR EDITORIAL PRODUCT MANAGER Angela Cesaro TECHNICAL LEAD Nicholas Sollecito
making such methods work with a sleep- SENIOR WEB PRODUCER Ian Kelly WEB PRODUCTION ASSOCIATE Eli Rosenberg
ing participant—perhaps awoken by a CONTRIBUTORS
EDITORIAL David Biello, W. Wayt Gibbs, Ferris Jabr, Anna Kuchment, Robin Lloyd,
prompt or beep and invited to report on Melinda Wenner Moyer, George Musser, Christie Nicholson, John Rennie, Ricki L. Rusting
ART Edward Bell, Bryan Christie, Lawrence R. Gendron, Nick Higgins
the dream—would be challenging indeed.
EDITORIAL ADMINISTRATOR Ericka Skirpan SENIOR SECRETARY Maya Harty
STRATEGIC CHOICE?
“A Matter of Choice,” by Peg Tyre, investi-
PRESIDENT
gates the results of school vouchers and Dean Sanderson
finds that they have led to lower scores in EXECUTIVE VICE PRESIDENT Michael Florek EXECUTIVE VICE PRESIDENT, GLOBAL ADVERTISING AND SPONSORSHIP Jack Laschever
PUBLISHER AND VICE PRESIDENT Jeremy A. Abbate
math and reading. I was dismayed that
MARKETING AND BUSINESS DEVELOPMENT
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Trump administration embraced them?”
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DIRECTOR, GLOBAL MEDIA ALLIANCES Ted Macauley
the proverbial gorilla in the room, which SENIOR ADMINISTRATOR, EXECUTIVE SERVICES May Jung
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rectly and systematically dismantled in MARKETING MANAGER Marie Cummings
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the name of private profits.
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Mohammad Babar J efferson City, Mo. ASSOCIATE VICE PRESIDENT, BUSINESS DEVELOPMENT Diane McGarvey
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In “Technology as Magic” [TechnoFiles], HEAD, COMMUNICATIONS, USA Rachel Scheer
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David Pogue invokes the name “Jeeves”
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thor P. G. Wodehouse, was not a butler. “If LETTERS TO THE EDITOR
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