In his post The evolutionary origins of human nature Razib writes about the new book by Richard Wrangham – Catching Fire: How Cooking Made Us Human:
Further reading:“Humans are a large animal with a very small gut, so we need to maximize the bang for the buck when it comes to what we eat. Unlike gorillas and to a lesser extent chimpanzees we just aren’t able to process enough low quality vegetable matter to keep ourselves going. Part of this also might be due to the fact that we have some serious energetic needs, our outsized brains require a lot of energy to keep them chugging along (as anyone with low blood sugar can tell you), and I also recall that our bipedal locomotion isn’t quite as efficient as that of the typical mammal’s at high speeds. Due to the content of the book it’s no surprise that they spend a fair time talking about the Raw Food movement. Wrangham’s thesis that we’re primed to consume cooked food because of our evolutionary background is obviously at odds with the theories which Raw Foodists propose (i.e., that in our “natural” state we didn’t cook foods). This is similar to some vegetarians who assert that man is naturally a plant eater. The very fact that we tend to crave meat and cooked foods would tend to argue against that, but there is plenty of evidence that humans have been omnivores who used fire to preprocess their food for a long time. But, the very difficulty of consumption of raw foods, or a high vegetable diet, is probably what makes them often a good choice for someone who wants to lose weight in an affluent society. In world with a surfeit of nutritional intakes putting foods on your plate which are relatively hard to digest (high fiber, etc.) and have a lower caloric intake per unit is a way to modulate consumption naturally (taking advantage of the very unnaturalness of what one is consuming).”