Book Review
What a brain: the remarkable evolution of what sets humans apart

By William Dietrich
Seattle Times staff reporter

	William Calvin
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Religion offers one answer, of course. But scientists seek a more empirical reason, if not answering "why" at least explaining "how."

Paleoanthropologists, for example, have shed light on primate evolution, skull development, human migration, and the first evidence of tools, religion and art. Geneticists have tried to trace our origins using maternal DNA.

Another tack is to apply our still-infant understanding of the brain in order to explain how the human mind likely developed. That has been the lifetime quest of University of Washington neurobiologist William Calvin, who as Seattle's Darwin has written a dozen books that revolve around that theme.

Author appearance William Calvin will read from "A Brief History of the Mind: From Apes to Intellect and Beyond," 7 p.m. Thursday, University Book Store, 4326 University Way N.E., Seattle, free (206-634-3400 or www.bookstore.washington.edu)

His latest, which provides an overview of the others, is "A Brief History of the Mind: From Apes to Intellect and Beyond" (Oxford University Press, $26). From explaining how human minds differ from those of dogs or chimpanzees to speculating on future mental evolution — which could both expand our capabilities and lead to a rise in mental illness — Calvin dances across 7 million years of evolutionary history.

He identifies two developments in particular that might have spurred brain evolution.

The first was the need to throw stones or spears to bring down game and ward off predators once climate change in Africa forced our ancestors from the forest to the grassy savanna. Throwing involves not just agility but mental calculation that could have helped hominid thinking about all kinds of things, Calvin theorizes.

The second, occurring just 50,000 years ago (a blink in evolutionary time), was the snowballing acquisition of language. Recent research in child brain development, the author explains, suggests that as children listened to primitive sentences, their brain neuron architecture may have adapted. When they in turn had children, their offspring inherited a natural ability for language that was superior to their parents. In essence, human brain "software" got a language upgrade through each generation.

Resulting communication changed everything, allowing the transmission of complex ideas. Civilization has been accelerating ever since.

We thus inherit brains that in some ways remain primitive. They are ruled by prehistoric emotions and did not evolve to grasp the big numbers of modern science and technology. Yet our brains did improve as we adopted language, so that while brain size hasn't grown in 100,000 years, its internal "wiring" or "software" is better. The result is that we have become quite-clever creatures who, because of our complex evolutionary ancestry, sometimes do astonishingly stupid things.

Calvin suspects the brain is still evolving as we try to grapple with technology and anxiety. We may get better at managing our emotions or remembering endless number sequences to access machines, but we may also suffer more mental disease as our savanna brains try to cope with a Buck Rogers world.

As a work of writing, "A Brief History of the Mind" is not just a summary of Calvin's thoughts; it is full of eloquent quotes from other thinkers. It has a good bibliography for readers who wish to explore this subject.

This book is not quite as smooth and accessible as some of Calvin's earlier books, however, nor as clearly organized. While the manuscript is brisk and marches logically through time, it often seems to be more an assembly of individual sections, jotted when the author had a bright idea or a spare moment, than a smoothly flowing organic whole.

Still, it is hard to imagine a subject of more fundamental interest to human beings. If you've ever wondered why you are who you are, "A Brief History of the Mind" is a good place to start.

Copyright © 2004 The Seattle Times Company