| The Magazine of the CALIFORNIA ACADEMY OF SCIENCES |
|
|
|
|
|
Reviews Evolution of Brains A Brain for All Seasons, by William H. Calvin. University of Chicago Press, Chicago, IL, 2002, 341 pp., $25 hardcover A Brain for All Seasons is the latest of a series of books on human evolution by William H. Calvin. Calvin is a lively writer and, according to the praise on the jacket, “a member of that rare breed of scientists who can translate the arcana of their fields into lay language.” A Brain is written as a series of email dispatches reporting on what Calvin has observed during various trips to Europe and Africa, and on over-the-pole flights between 1999 and 2001. The book’s main premise is to explore the ways in which historical climatic cycles of “cool, crash and burn” have driven the enormous increase in brain size and complexity in humans. Unfortunately, it fails to deliver, and it fails badly. The core of the book is built around the text of “The Great Climate Flip-Flop,” a very good piece written by Calvin in 1998 for the Atlantic Monthly. Eager to recycle and extend the reach of the article, Calvin has buried it within chapters detailing his thoughts on the influences that environmental change has had on the course of human history. The marriage between the article and the rest of the book’s content is frankly a shotgun arrangement. While reading A Brain, I felt that I was sitting at the dinner table chatting to Calvin about human evolution. Now, some people like books that are chatty, rambling, and filled with the occasional burp and tangent, but I’m a bit old-fashioned, and don’t think that the banter of dinner table conversation makes for a good science book. The book is structured like a shopping mall, with lots of meaningless variety, no logical structure, and enough mental distractions to transform the reader into one terpsichorean twitch. By the time I had finished the first 50 pages, I had careened from a reverie on Darwin’s garden through the highlights of the last 5 million years of human evolution. I had read some reflections on chimp tool-making, an exploration of the human predilection for open landscapes, speculation on the connection between human language and throwing abilities, a summary of biotic evolution since the Big Bang, and an explication of the mechanisms involved in very rapid climatic change. All this was interspersed with observations of German V-2 rocket-launching sites from a passing train window, and notes on a meal in a Parisian cafe. Readers who know something about the science that Calvin is writing about will recoil upon reading statements like “Back to 25 million years ago, apes evolved from Old World monkeys. And at 50 million years ago, we’re all still monkeys getting larger after the big extinction at 65 million years ago which killed off the dinosaurs” (p. 53). Those of us who spend our days trying, by one means or another, to teach evolution, turn into reeling nut cases when we read stuff like this. Apes did not evolve from Old World monkeys 25 million years ago; apes and monkeys shared a common ancestor 25 million years ago. There is a subtle, but critical, difference between these statements. At 50 million years ago, we weren’t all monkeys getting larger; the major lineages of primates—prosimians, tarsiers, and anthropoids—had emerged and embarked on their own very distinctive evolutionary trajectories. Being factually correct doesn’t have to mean being pedantic, but it is a requirement for good scientific writing. One of Calvin’s subthemes is that humans were able to survive the vicissitudes of climate change because their early economies were centered around resources located in or near bodies of water. After flirting with the aquatic ape theory for the evolution of human bipedalism, he develops the idea that early humans survived by engaging in extensive predation of animals at waterholes. The stone handaxes found in and near lake margins amply demonstrate this. Fair enough, but Calvin goes on to describe how handaxes started out as throwing implements, and only later developed into multifunctional tools. He then connects tool making and tool throwing to the development of linguistic abilities, but by this point he had lost this reviewer completely. The most frustrating thing about A Brain is that Calvin never really gets to the point of how brain expansion is connected to sudden climate change. This failure left me feeling frightfully shortchanged at the end of the book. But the most unfortunate thing of all about Calvin’s book is that it could have been very good. With more vigorous editing and attention to detail, Brain could have been a vivid tour de force in which the relationship between human evolution and climate change was explored in a way that could be grasped by the general reader. Nina Jablonski Love in the Beginning Love at Goon Park: Harry Harlow and the science of affection, by Deborah Blum. Perseus Publishing, New York, NY, 2002, 336 pp., $26 hardcover Less than a century ago, love was truly a four-letter word to scientists. When it came to the feelings between parent and child, the term rang even more alarm bells. As hard-nosed observers, they called it attachment, proximity, even “conditioned response.” In Love at Goon Park, Pulitzer Prize-winning science writer Deborah Blum follows the life of psychologist Harry Harlow, the man who taught the scientific world about love. (to page 52) Blum first encountered Harlow while researching her book The Monkey Wars, which chronicles the battle over primate research. Embarking on the scientist’s biography, she wasn’t sure if she was going to like him. She knew “he would be a sharp-edged subject—fascinating and troubling, and underneath the prickles the velvety gleam of brilliance.” Along with the compelling details of this contradictory man’s life, Blum’s descriptions make even the minute give-and-take of a developing field riveting. Harlow was an unlikely man to champion the existence of love. He drank heavily, and was a distant father and husband who spent more time in the lab than with his children. At work, he wrote messages to students and colleagues in verse while fueling feminists’ ire with chauvinistic comments. Yet he challenged the majority of scientific minds of his time, which insisted that love between parent and child created only disease and dependence. Blum sets out his experiments unflinchingly. While Harlow’s first entry into primates began with intelligence testing, his most controversial—and most influential—work delved into relationships between mother and child. He separated baby monkeys from their mothers and found they clung to cloth bundles as ballast in a world of frightening newness. Far from showing that real mothering caused overdependence, Harlow’s experiments suggested a mother’s care provides a stepping-stone for venturing into other healthy relationships. In addition to observing the links love creates, Harlow also studied the frightening aspects of love denied. Mechanical “monster” mothers shook and tossed their babies aside—yet the young monkeys kept crawling back to the twisted love they knew. As Harlow himself sank into depression during the fatal illness of his second wife, he sentenced his monkeys to isolation chambers which he termed “pits of despair.” Monkeys subjected to these experiments sat contorted and shaking, and became mothers even more terrible than the ones built by the researchers. Blum enters the ethical arena of Harlow’s work in the final chapter. But for some readers, this may not be enough to address the disturbing questions raised by Harlow’s research methods. Still, Harlow was responsible for yet another insight into the nature of relationships. He retrieved the monkeys from the pit of despair, and slowly introduced them to three-month-old monkeys,which cuddled against their shivering cagemates. After months of this love therapy, the damaged animals started to interact, then play, then assimilate into normal monkey life. Harlow had uncovered yet another aspect of this unspeakable emotion—recovery. Cameron Walker Climbing to Light Sierra: Notes and Images from the Range of Light, by James Martin. Sasquatch Books, Seattle, WA, 2002, 150 pp., $19.95 paper. As a longtime devotee of High Sierra peaks, James Martin makes fine use of his vast climbing experience and photographer’s eye to bring this rarified world to readers of Sierra. It’s a rare glimpse of the intricate dance between rock and light, and also a taste of the stories that a climber accumulates. Writing simply and persuasively, Martin tells of humbling encounters with his own naivete as a young man, when he backpacked 175 miles in cotton clothing, and almost no food, as an unauthorized addition to Ansel Adams’ photography classes in Yosemite. Through words and images, Marin shows us the excitement and ethereal beauty of this realm of rock and ice at sunset or during a break in a storm. Along the way, he adds some nicely written chapters on the geologic story of the Sierra Nevada to give the book a solid balance of personal encounter and detailed science. But the most compelling aspect of the book is Martin’s photography. Colorful yet moody, expansive as well as particular in detail, these high-quality photographs were taken while dangling from climbing ropes high up among hard to reach summits and interior wilderness regions that few eyes will witness firsthand. The Sierra Nevada is a different landscape when seen through the scope of Martin’s rangefinder, and that’s a good reason to search for Sierra. David Lukas |