Cookito* Ergo Sum

As early humans developed the ability to cook foods, which could have been anywhere from 300,000 to 1.9 million years ago, human physiology began to evolve. Humans began to have smaller mouths and jaws and shorter digestive systems than apes. "We are the cookivore," Wrangham observed, because now humans must consume softer foods, low-bulk and high-energy diets. "We have more energy, but less digestive ability," he continued.
LINK

*Cookito is a bad Latin pun on Cogito that I just made up.
(When Glenn Reynolds links to a something, I don't usually bother. It's like somebody mumbling in the midst of a crowd. But this is right down my alley.)