Last Ape Standing: The Seven-Million-Year Story of How and Why We Survived (35 page)

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.

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.

“Why Music?”
Economist
, December 18, 2008, 1–1.
http://www.economist.com/node/12795510
.

“Why We Are, as We Are.”
Economist
, December 18, 2008.
http://www.economist.com/node/12795581
.

Wills, Christopher.
The Runaway Brain: The Evolution of Human Uniqueness
. New York: HarperCollins Publishers, 1993.

Wilson, David Sloan.
Evolution for Everyone: How Darwin’s Theory Can Change the Way We Think About Our Lives
. New York: Bantam Dell, 2007.

Wilson, Edward O.
On Human Nature
. Trade paperback. Cambridge, MA: Harvard University Press, 1978.

Wong, K. “Who Were the Neanderthals?”
Scientific American
289 (2003): 28–37.

Zak, Paul J. “The Neurobiology of Trust.”
Scientific American
298.6 (2008): 88–92, 95.

Zilhão, et al. “Symbolic Use of Marine Shells and Mineral Pigments by Iberian Neanderthals.”
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Zimmer, Carl. “Siberian Fossils Were Neanderthals’ Eastern Cousins, DNA Reveals.”
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^a
Ants.

^b
Many more human species may have existed at this time, but the farther back in time you go, the more likely those creatures lived in rain forests, and the less likely conditions were optimal for creating fossils.

^c
See pages 37–38 of
Thumbs, Toes, and Tears: And Other Traits That Make Us Human
for Bolk’s complete list.

^d
Life evolved soon after Earth itself came into existence some four billion years ago. The first cells were prokaryotic. The best guesses for the time when eukaryotes (cells with mitochondria) evolved range from just below 2.0 billion years to around 3.5 billion years before the present. The early fossil record for single–celled organisms, as you might expect, is sparse, so it’s tough to set the exact date of this remarkable bargain.

^e
When the ancient Carthaginian explorer Hanno the Navigator came across a group of what he called savage men and hairy women in West Africa twenty-five hundred years ago, he wasn’t sure if they were human, but the difference between them and him was clearly large. His interpreters called the creatures
Gorillae
, from which we later derived the term
gorilla
. It’s possible that’s exactly what Hanno had encountered.

^f
Aurochs were a type of now–extinct, large, wild cattle that inhabited Europe, Asia, and North Africa. They survived in Europe until 1627, when the last recorded member of the species, a female, died in the Jaktorów Forest, in Poland.

^g
The word is still out on Denisovans and the Red Deer Cave people. Even
Homo floresiensis
. Denisovans appear to also have descended from
Homo heildelbergensis
.

^h
A term coined by evolutionary biologist Richard Dawkins in his book
The Selfish Gene
.

ⁱ
This is the hypothesis of evolutionary theorist Oliver Curry of the London School of Economics.

^j
Conducted by the American Psychological Association, 2010.

^k
A term coined in my previous book
Thumbs, Toes, and Tears: And Other Traits That Make Us Human
.

Chip Walter is founder of the popular website AllThingHuman.net, a former CNN bureau chief, and feature film screenwriter. He has written and produced several award–winning science documentaries for PBS, in collaboration with the National Academy of Sciences, including programs for the Emmy Award–winning series
Planet Earth
and
Infinite Voyage
. Chip’s science writing has embraced a broad spectrum of fields and topics. He is the author of
Space Age
, the companion volume to the PBS series of the same title;
I’m Working on That
, written with William Shatner; and
Thumbs, Toes, and Tears—And Other Traits That Make Us Human
. His books have been published in six languages.

Chip’s articles have also been featured in the
Economist
,
Scientific American
,
Scientific American Mind
,
Slate
, the
Washington Post
, the
Boston Globe
,
Discover
magazine, and many other publications and websites. He is currently an adjunct professor at Carnegie Mellon University’s School of Computer Science and Entertainment Technology Center. He lives in Pittsburgh with his wife, Cyndy, and their children Molly, Steven, Hannah, and Annie.

Thumbs, Toes, and Tears: And Other Traits That Make Us Human

I’m Working on That
, written with William Shatner

Space Age

Paranthropus aethiopicus

This creature was among three species of “robust” humans, some of whom roamed the plains of Africa for as many as a million years. They might have outcompeted the line of primates that eventually led to us, but our direct ancestors took an odd evolutionary turn that lengthened our childhoods and profoundly changed human evolution. (See Chapter 2: “The Invention of Childhood.”)
Original artwork by Sergio Pérez.

Homotherium—Big Cat of the Ancient Savanna

Life on Africa’s ancient savannas had to have been terrifying. The humans who roamed and foraged there between 5 million and 1.5 million years ago probably spent a good deal of their time avoiding big cats like this one, a precursor of today’s lions, panthers, and tigers. The danger they presented further bonded early humans, making cooperation among them more important than ever, one reason we are so social today. (See Chapter 2: “The Invention of Childhood.”)
Homotherium © 2005 Mark Hallet.

Lake Turkana—An Evolutionary Garden of Eden?

Today Lake Turkana is the world’s largest alkaline lake, but millions of years ago it was the garden spot of Africa and home to ancient human species of all kinds, including the line that likely led to us. (See Chapter 3: “Learning Machines.”)
Photo credit: Yannick Garcin.

The Boy Who Changed Our View of Human Evolution

Also known as Nariokotome Boy, this young man met his end 1.5 million years ago. Luckily, and remarkably, most of his skeleton survived, making him one of the most important paleoanthropological finds ever. His teeth and bones have illuminated the mysterious evolution of our long childhoods and the crucial role it played in our survival. (See Chapter 2: “The Invention of Childhood.”)
Photo credit: Look Sciences/Photo Researchers.

The Ancient Continents of Sunda and Sahul

Fifty thousand years ago waves of modern humans began making their way out of Africa, scattering in all directions. Some tribes wandered to Australia, more than ten thousand miles away. They were able to make that journey because forty-five thousand years ago a swing to frigid climate locked oceans of water in earth’s polar caps and dropped global sea levels. That created these immense continents in the Indian and Pacific oceans which are today submerged: Sunda and Sahul. Across these landmasses (with some short hops by sea) early humans made their way to the plateaus and mountains of western Australia, the ancestors of today’s Australian Aborigines. (See Chapter 5: “The Everywhere Ape.”)
Based on original artwork by Maximilian Dörrbecker.

The Scattering of the Human Race