A Brain for All Seasons: Human Evolution and Abrupt Climate Change [Hardcover]

Calvin sets the scene at the time when climate changes forced the shrinking of the forest cover in East Africa. Our barely upright ancestors, in coping with the changing environment, learned survival skills on the savannah, then spread out over the globe. During our migrations, various new climatic conditions were being established . The suture of Central America joining North and South America set new wind and current patterns around the globe. The resulting North Atlantic Current [the Gulf Stream] and the temperature and salinity exchanges in that ocean have proven a major factor in climate. Calvin examines what is known about these mechanisms and the impact of variations. The most significant new knowledge refutes the established idea that climate changes gradually. Sudden, wild "flips" of temperature, rainfall and snow cover are now seen as the norm, not as aberrations. Change isn't on the order of centuries, but in years.

Calvin's technique of presenting his ideas is as novel as his thesis. Each chapter is an "electronic seminar" with "lectures" and questions arriving for the reader's scrutiny from locations all over the globe. Calvin thus presents himself as a field investigator, relating what on-site researchers are revealing. And much, indeed, is being exposed for assessment. Records from Greenland ice and other sources indicate "chattering" patterns of weather change. These and other finds are related and discussed. And presented for the reader to ponder. If the text doesn't give you reason to pause and reflect, there are numerous striking photographs and diagrams to seize your attention. A Glossary and excellent Further Reading section complete a work of striking significance. If you delay reading this, you may find yourself having to don mittens to take it up. Read it NOW! [stephen a. haines - Ottawa, Canada]

On the other hand, the writing is conversational and detailed, thorough and startling. This is one of those books "everybody should read," because the information in it - particularly in the last third - is so incredibly critical to the fate and future of the human race.

Calvin has done one of the best jobs I've seen of explaining how and why the Atlantic currents transport heat and salt - and what happens when they shut down, plunging the entire world into an ice age in as little as 3 to 12 years. (This isn't a just a future threat - it's also an observation of times past. Every ice age has started and ended in fewer than a dozen years!)

Calvin tells us in detail how Europe will be devastated by the next ice age, how our SUV usage today in North America is leading us right to it (and much sooner than most think), and - most amazingly - offers some specific suggestions about things that can be done to stop it (like daming up some fjiords in Greenland and dynamiting others).

Along the way, we also get a completely new view of human evolution, based in the whiplash environment humans survived for the past 200,000 years.

This book is brilliant, and I highly recommend it. Just be sure to mark up the pages as you read them, because that's the only way you'll be able to find things later when you try to explain it to your friends (as you will want to do!).

The book is also incredibly repetitive, and could have been at least 100 pages shorter without losing a thing. I wrote a longer review of it elsewhere; if I hadn't been planning to do that I never would have managed to finish the book at all. Even worse, it's written in a silly 'e-seminar' format--which means that Calvin starts every chapter with a sort of email header that also includes, for some reason, latitude and longitude information. The effect is as ridiculous as John Barth's text hypertext in _Coming Soon_. The format also might explain Calvin's chatty style, which might appeal to some people but which I found rather grating and demeaningly pedagogical after about twenty-five pages.