Why do we cook food? So we can eat it faster, it says here.
"I think it needs salt."
One great thing about paleoanthropology is that the paucity of evidence on many points gives free rein to fascinating speculation. Take, for example, the reports today in which it is hypothesized that because Homo erectus teeth show a reduction in size from teeth of older hominin species, that means that H. erectus cooked its food. That was nearly two million years ago.
The long-time guru of cooking-as-key-evoloutionary-step is Richard Wrangham, at Harvard. He and colleague Chris Organ write in the current PNAS. Their research consisted of calculating the amount of time it takes a primate to chew its food and comparing it to the animal’s body size. They found that if humans had to chew raw food, it would take 48 percent of their day, which is about what it takes similarly sized apes. But, in fact, we devote only about 4.7 percent of our time to chowing down.
So cooking saved time and allowed us to get by with smaller teeth that don’t have to stand up to so much grinding. And the spare time, the authors suggest, gave us time to think, invent tools and get smarter, eventually to invent more ways to spend time on the cooking rather than the eating. Actually, the authors didn’t suggest that last part.
Jennifer Welsh of LiveScience, as picked up by MSNBC.com, offered the only account we could find of a weakness in the claim, namely that nobody has found evidence of fire pits or hearths as old as the claimed antiquity of cooking
A sampling of other stories: Rachel Ehrenberg in Science News; Cynthia Graber has a Scientific American podcast; Carl Bagh of the International Business Times, which seems to have a version of almost every science story, goes overboard in writing that the new study “confirms” that H. erectus was cooking food but he includes a goodly amount of background material.
-Boyce Rensberger
