Scientific American - November 2011.pdf

(44502 KB) Pobierz

Planetary Science

Uncovering

Mars’s Secrets

Energy

The Truth

about Fracking

Environment

Sustainably

Doubling Food

Production

November 2011 ScientiicAmerican.com

THE

FIR ST

AMERICANS

Trailblazers arrived

far earlier than

previously thought.

Who were they?

© 2011 Scientific American

782179130.217.png

782179130.228.png

782179130.239.png

782179130.250.png

782179130.001.png

782179130.011.png

782179130.022.png

782179130.033.png

782179130.043.png

782179130.054.png

782179130.065.png

782179130.076.png

782179130.087.png

782179130.098.png

782179130.109.png

782179130.120.png

782179130.131.png

782179130.142.png

782179130.153.png

782179130.164.png

782179130.175.png

782179130.184.png

782179130.185.png

782179130.186.png

782179130.187.png

782179130.188.png

782179130.189.png

782179130.190.png

782179130.191.png

782179130.192.png

782179130.193.png

782179130.194.png

782179130.195.png

782179130.196.png

782179130.197.png

782179130.198.png

782179130.199.png

782179130.200.png

782179130.201.png

782179130.202.png

782179130.203.png

782179130.204.png

782179130.205.png

782179130.206.png

782179130.207.png

782179130.208.png

782179130.209.png

782179130.210.png

782179130.211.png

782179130.212.png

782179130.213.png

782179130.214.png

782179130.215.png

782179130.216.png

782179130.218.png

782179130.219.png

782179130.220.png

782179130.221.png

782179130.222.png

782179130.223.png

782179130.224.png

782179130.225.png

782179130.226.png

782179130.227.png

782179130.229.png

782179130.230.png

782179130.231.png

782179130.232.png

782179130.233.png

782179130.234.png

782179130.235.png

782179130.236.png

782179130.237.png

782179130.238.png

782179130.240.png

782179130.241.png

782179130.242.png

782179130.243.png

782179130.244.png

782179130.245.png

782179130.247.png

782179130.248.png

782179130.249.png

782179130.251.png

782179130.252.png

782179130.253.png

782179130.254.png

782179130.255.png

782179130.256.png

782179130.257.png

782179130.258.png

782179130.259.png

782179130.260.png

782179130.002.png

782179130.003.png

782179130.004.png

782179130.005.png

782179130.006.png

782179130.007.png

782179130.008.png

782179130.009.png

782179130.010.png

782179130.012.png

782179130.013.png

782179130.014.png

782179130.015.png

782179130.016.png

782179130.017.png

782179130.018.png

782179130.019.png

782179130.020.png

782179130.021.png

782179130.023.png

782179130.024.png

782179130.025.png

782179130.026.png

782179130.027.png

782179130.028.png

782179130.029.png

782179130.030.png

782179130.031.png

782179130.032.png

ON THE COVER

For years the conventional wisdom on the peopling of the

New World held that the so-called Clovis hunters were

the irst Americans, arriving some 13,000 years ago. Now

new evidence shows conclusively that humans reached

the Americas far earlier than previously thought, raising a

host of questions about who these pioneers were and

how they got here. Image by Viktor Deak.

November 2011 Volume 305, Number 5

FEATURES

ARCHAEOLOGY

36 The First Americans

Who were they, and how did they get here?

In light of new evidence, scientists are rethinking

long-held ideas. By Heather Pringle

PLANETARY SCIENCE

46 Digging Mars

The leader of the Mars Phoenix mission reviews

its indings and looks ahead to the Mars Science

Laboratory, now setting out to follow up.

By Peter H. Smith

54 The Smallest Astronauts

Could meteorites have seeded Earth with life?

A space probe illed with microbes will tell us.

By David Warmlash

EXPERIMENTAL PHILOSOPHY

56 Thought Experiments

Philosophers are conducting scientiic experiments

on the nature of free will. By Joshua Knobe

SUSTAINABILITY

60 Can We Feed the World

and Sustain the Planet?

A ive-step global plan ofers a way forward.

By Jonathan A. Foley

GEOLOGY

66 Sleeping Giant

A restive volcano is inspiring a rare collaboration be-

tween Chinese and Korean scientists. By Sid Perkins

BIOTECHNOLOGY

68 The Wipeout Gene

Deep in the Mexican jungle, genetically modiied

mosquitoes could exterminate native species that

spread disease. By Bijal P. Trivedi

COMPUTING

76 A Formula for Economic Calamity

Despite the lessons of the 2008 collapse,

Wall Street is betting our future on limsy science.

By David H. Freedman

ENERGY

80 The Truth about Fracking

What we know, and don’t know, about the dangers

of hydraulic fracturing. By Chris Mooney

DIAGNOSTICS

86 The Medical Sleuth

NIH investigator William A. Gahl unravels the

cause of illnesses that have stumped other doctors.

Interview by Brendan Borrell

68

2 Scientiic American, November 2011

Photograph by David Liittschwager

© 2011 Scientific American

782179130.034.png

782179130.035.png

782179130.036.png

782179130.037.png

782179130.038.png

782179130.039.png

782179130.040.png

782179130.041.png

782179130.042.png

782179130.044.png

782179130.045.png

782179130.046.png

782179130.047.png

782179130.048.png

782179130.049.png

782179130.050.png

782179130.051.png

782179130.052.png

782179130.053.png

782179130.055.png

782179130.056.png

782179130.057.png

782179130.058.png

782179130.059.png

782179130.060.png

782179130.061.png

782179130.062.png

782179130.063.png

782179130.064.png

782179130.066.png

782179130.067.png

782179130.068.png

782179130.069.png

782179130.070.png

782179130.071.png

782179130.072.png

782179130.073.png

782179130.074.png

782179130.075.png

782179130.077.png

782179130.078.png

782179130.079.png

782179130.080.png

782179130.081.png

782179130.082.png

782179130.083.png

782179130.084.png

782179130.085.png

782179130.086.png

782179130.088.png

782179130.089.png

782179130.090.png

782179130.091.png

782179130.092.png

782179130.093.png

782179130.094.png

782179130.095.png

782179130.096.png

782179130.097.png

782179130.099.png

782179130.100.png

782179130.101.png

782179130.102.png

782179130.103.png

782179130.104.png

782179130.105.png

782179130.106.png

782179130.107.png

782179130.108.png

782179130.110.png

782179130.111.png

782179130.112.png

782179130.113.png

782179130.114.png

782179130.115.png

782179130.116.png

782179130.117.png

782179130.118.png

782179130.119.png

782179130.121.png

782179130.122.png

782179130.123.png

782179130.124.png

782179130.125.png

782179130.126.png

782179130.127.png

782179130.128.png

782179130.129.png

782179130.130.png

782179130.132.png

782179130.133.png

782179130.134.png

782179130.135.png

782179130.136.png

782179130.137.png

782179130.138.png

782179130.139.png

782179130.140.png

782179130.141.png

782179130.143.png

782179130.144.png

782179130.145.png

782179130.146.png

782179130.147.png

782179130.148.png

782179130.149.png

782179130.150.png

782179130.151.png

782179130.152.png

782179130.154.png

782179130.155.png

782179130.156.png

782179130.157.png

782179130.158.png

782179130.159.png

782179130.160.png

782179130.161.png

782179130.162.png

782179130.163.png

782179130.165.png

782179130.166.png

782179130.167.png

782179130.168.png

782179130.169.png

782179130.170.png

782179130.171.png

782179130.172.png

782179130.173.png

782179130.174.png

782179130.176.png

782179130.177.png

782179130.178.png

782179130.179.png

782179130.180.png

782179130.181.png

782179130.182.png

782179130.183.png

Plik z chomika:

Inne pliki z tego folderu:

Scientific American's Ask the Experts Answers to The Most Puzzling and Mind-Blowing Science Questions.pdf (4677 KB)
Scientific American - Mind - February 2010.pdf (7637 KB)
Scientific American Inventions and Discoveries - Rodney Carlisle.pdf (6190 KB)
Scientific American - December 2012.pdf (23337 KB)
Scientific American - October 2012.pdf (35301 KB)

Inne foldery tego chomika:

Zgłoś jeśli naruszono regulamin