NPR’s most e-mailed story of the past week discussed the topic of how eating meat made humans smarter. It included an interview with Richard Wrangham, whose book Catching Fire: How Cooking Made Us Human I reviewed last year.
It made me realize that my science blog readers might appreciate my revisiting some reviews of books that are still of interest. I’ll start with this one, and if there is sufficient interest in my posting such reviews, I’ll try to do so once or twice a month. Let me know of your interest by commenting here or by sending me an e-mail. If you want to request a particular review, check out the Science Shelf website to see what more than ten years of book reviewing can add up to.
Anyway, here’s my review of Catching Fire: How Cooking Made Us Human by Richard Wrangham (Basic Books, 312 pages, $26.95, June, 2009)
(This review is the copyrighted property of Alfred B. Bortz. Individuals may print single copies of reviews or columns for their own use. For permission to publish or print multiple copies, please contact the author by e-mail.)
To hear Harvard anthropologist Richard Wrangham tell it in Catching Fire: How Cooking Made Us Human, “…the transformative moment that gave rise to the genus Homo, one of the great transitions in the history of life, stemmed from the control of fire and the advent of cooked meals” almost two million years ago.
Wrangham looks at the advantages of cooked food from an evolutionary perspective. As a new, brainier species evolves, its body has to reallocate to the brain some of the nutrition and energy consumed by other body parts. For that species to thrive without losing other capabilities, it must extract more net resources from its food.
Cooking makes that possible by transforming food into a form that the body digests more efficiently. The same amount of cooked food can supply not only the nutrition to support the same body that the raw food could, but it can also feed a larger brain.
Wrangham argues that cooking launched early hominids onto an evolutionary path that changed not only brains but also bodies and social lives. Their jaws and digestive systems became smaller, paving the way for the evolution of still larger brains.
At some point, hominid bodies morphed into modern human form, and cooking morphed from an advantageous technology into one that our species could not live without. We became “the cooking apes, the creatures of the flame.”
For those readers who argue that we could survive on raw food alone, Wrangham describes the tribulations of people throughout history who have temporarily survived on uncooked or dried foods.
Even today, when top quality produce is readily available, “raw-foodists” are chronically undernourished. The most extensive research is the Giessen (Germany) Raw Food study of 513 individuals who ate between 70 and 100 percent raw diets. Writes Wrangham, “The scientists’ conclusion was unambiguous: ‘a strict raw food diet cannot guarantee an adequate energy supply.'” The energy shortage “is biologically significant…. Among women eating totally raw diets, about 50 percent entirely ceased to menstruate.”
Many of Wrangham’s conclusions are bound to be controversial. He devotes two chapters to the social order, including arguments that cooking has led to a sexual division of labor and a degree of male dominance bordering on the abusive.
The epilogue recommends changes in the standard method of computing the caloric content of cooked food. Modern living, including the technology of cooking, has evolved faster than our bodies. His conclusion: “We must find ways to make our ancient dependence on cooked food healthier.”
Fred Bortz is the author of numerous science books for young readers.
Readers of Catching Fire may also enjoy discovering other books on evolution and human origins featured at The Science Shelf.