Email Calvin || Glossary || Book's Table of Contents || Calvin Home Page  


William H. Calvin, A Brain for All Seasons:  Human Evolution and Abrupt Climate Change (University of Chicago Press, 2002). See also

copyright ©2002 by William H. Calvin
ISBN 0-226-09201-1 (cloth)    GN21.xxx0     
Available from or University of Chicago Press.
Webbed Reprint Collection
This 'tree' is really a pyramidal neuron of cerebral cortex.  The axon exiting at bottom goes long distances, eventually splitting up into 10,000 small branchlets to make synapses with other brain cells.
William H. Calvin

University of Washington
Seattle WA 98195-1800 USA

Return to the final chapter


As I said in the postscript for my 1986 book, The River That Flows Uphill, “Writers sometimes feel as if they have been taken over by a book: it develops a life of its own, proclaims its own imperatives, almost writes itself once the framework is established; one has to somehow live up to its expectations.”

     The present framework is an amalgamation of various European and African trips, meetings, and over-the-pole flights between 1999 and 2001, rearranged to suit the thematic development.  It took me several years to discover this e-seminar framework (I’ve never actually taught a seminar this way), as I tried to figure out how to utilize my well-edited Atlantic Monthly cover story, “The great climate flip-flop,” in the more general context of how our ancestors evolved a chimpanzeelike brain into our present-day model.  The most significant of the consequent misrepresentations is actually of me as the narrator.  I certainly don’t write emails which achieve the literary levels that rewriting and editors can produce.

     My long interest in the brain-enhancing aspects of paleoclimate is where that 6,600-word Atlantic Monthly article came from, though all the brain-related materials were edited out, to focus solely upon the climate history and their oceanographic mechanisms.  There’s a problem with doing brain evolution too briefly, as someone (such as the climate change skeptics who so predictably enjoy being “tough-minded”) will mistakenly conclude that climate catastrophes are “a good thing.”

     One problem I had, in writing the first draft of the Atlantic article in 1997, was that the facts alone were pretty depressing.  These abrupt coolings were far worse than global warming, and far more frequent than meteor strikes and major volcanic coolings.  But I gradually realized that I had a much more hopeful attitude towards the abrupt climate prospects – it wasn’t at all like my “Why worry” attitude towards the usual potential catastrophes such as earthquakes, meteors, and Mount Rainier burying Seattle under a mud flow.

     In analyzing this mismatch between the bare facts and my gut feelings, I realized that I’ve seen the practice of medicine change over the three decades that I’ve been on a medical school faculty, and it seemed to me that we ought to be able to devise interventions for climate change that are analogous to what we’ve done with vaccines and antibiotics – that we stand an excellent chance of being able to understand what’s going on with abrupt climate change, a good chance of being able to devise strategies that “buy time,” and a fair chance of developing a “vaccine” technology that can stabilize the climate so that it doesn’t pop back into the cool-and-dry mode.

     In the aftermath of the Atlantic article, when answering letters to the editor, something else fell in place.  Too many people were trying to simplify things by dwelling on “the most likely scenario” for the next century.  That’s a classic mistake, one that physicians are trained not to get trapped by.  Medical schools have institutionalized forums found in few other segments of our society, just to keep driving this home.  The clinical pathological conference is where the pathologist reveals the results of the biopsy or autopsy and everyone discusses what mistakes were made in diagnosis and treatment.  Thinking back, I realized that a lot of mistakes were made simply because referring physicians hadn’t been able to think beyond the “most likely outcome.”  There, too, things have changed in recent decades and I have some hopes that a science of climate will adopt some of the ways of thinking seen in more developed areas of high-risk management.

     Over the last decade, I’ve also gotten to know a lot of futurists, people used to thinking about the future – and about how to frame the issues.  That’s where the last part of this book came from, my attempts to sketch out some simple-minded interventions and my suggestions for how we can now test out such interventions on the computer models of climate change.  Stabilizing the climate is one of civilization’s great tasks, one that deserves much attention in the twenty-first century.






I have a lot of people to thank within the geoscience community, those who have taken the trouble to help educate an interloper from biophysics and neurobiology.  The easiest to identify is the editor of Quaternary Research, Stephen C. Porter, because year after year he organized a lecture series at the University of Washington’s Quaternary Research Center, which is where I met such people as the glaciologist Hans Oeschger in 1984 (that’s where I first heard about abrupt climate change)  and the archaeologist Glynn Isaac in 1983 (which is where I saw the shatter-and-search toolmaking demonstrated).

     I owe particular thanks to William Whitworth, then editor of the Atlantic Monthly, for twisting my arm back in April, 1997.  At a time when most news media were simply not reporting the abrupt climate change story, he had gotten wind of it, asked Freeman Dyson who might be able to write it, and phoned me.  I spent two weeks suggesting climate researchers who could do a better job, but finally relented – mostly because I had been telling all my friends that someone ought to write this story for nonscientists, that it was a scandal that it had gone largely unreported for ten years despite all the news-feature stories in Science and Nature.  Toby Lester and the other editors at the Atlantic did a wonderful job of improving my prose; I hope that not too many of their improvements were lost in my conversion to the present travelogue format.

     Authors find it difficult to get useful feedback on first drafts and so I especially thank my volunteer readers for commenting so effectively:  Ingrith Deyrup-Olsen, Penn Goertzel, Blanche and Seymour Graubard, Katherine Graubard, Daniel K. Hartline, Conway Leovy, India Morrison, Gordon Orians, Sonia Ragir, Susan B. Rifkin, Peter G. Rockas, and Barbara Sherer.  Two of the anonymous reviewers for the University of Chicago Press were especially helpful with climate and anthropological detail.

     In addition, I was aided by useful conversations with (well, it actually goes back to Melville Herskovits and Louis Leakey in 1959) Richard Alley, Elizabeth Bates, Wolf Berger, Derek Bickerton, Barry Bogin, Stewart Brand, Wally Broecker, Peter Clarke, Ronald Clarke, Iain Davidson, Terry Deacon, Derek Denton, Brian Fagan, Dean Falk, Stephen Jay Gould, William Hopkins, Richard Hutton, Glynn and Barbara Isaac, Harry Jerison, Donald Johanson, Kenneth Kidd, Richard G. Klein, Mel Konner, Kathleen Kuman, Meave Leakey, Elizabeth F. Loftus, Linda Marchant, John Maynard Smith, William McGrew, Charles Minzel, Jim Moore, Solene Morris, Toshisada Nishida, Hans Oeschger, Jay Ogilvy, David Perlmutter, Ray Pierrehumbert, Steve Pinker, Stefan Rahmstorf, Peter Rhines, Peter Richerson, Duane Rumbaugh, Ed Sarachik, Sue Savage-Rumbaugh, Margaret J. Schoeninger, Peter Schwartz, Eugenie Scott, Jeff Severinghaus, Pat Shipman, Eric Steig, Thomas Stocker, Ian Tattersall, Phillip V. Tobias, Ajit Varki, Frans de Waal, Ed Waddington, Alan Walker, Robert W. Walter, Peter Ward, Andrew Weaver, Christopher Wills, Bernard Wood, and Richard Wrangham.

     I have benefited much from a book-writing stay at the Helen R. Whiteley Center at the University of Washington’s Friday Harbor Laboratories and from workshops sponsored by the Mathers Foundation and the Foundation for the Future.


On to the Glossary

Notes and References
corresponds to 
pages 297 to 300 of the printed book)

Copyright ©2002 by
William H. Calvin

The nonvirtual book is
available from
or direct from
 University of Chicago Press

  Book's Table of Contents  

  Calvin Home Page

All of my books are on the web.
You can also click on a cover for the link to

Conversations with Neil's Brain:  The Neural Nature of Thought and Language (Calvin & Ojemann, 1994)

The Cerebral Code:  Thinking a Thought in the Mosaics of the Mind (1996)

How Brains Think:  Evolving Intelligence, Then and Now (1996)

Lingua ex Machina:  Reconciling Darwin and Chomsky with the Human Brain (Calvin & Bickerton, 2000)

The six out-of-print books are again available via Authors Guild reprint editions,
also available through (click on cover):

Inside the Brain

The Throwing Madonna:  Essays on the Brain

The River That Flows Uphill


The Cerebral Symphony

The Ascent of Mind

How the Shaman Stole the Moon