In this article, the argument presented is that cooking is at least partially responsible for human brain development. Interesing.
from New Scientist
Organ and Charles Nunn, also of Harvard, had predicted that if humans are uniquely adapted to eating cooked food, then we should spend far less time chewing than other primates, as cooked food tends to be softer than raw food. To test this, they gathered data from various primate species and looked at the correlation between chewing time and body size, taking into account how the different species were related to each other.
A primate species of our size should, in theory, spend 48 per cent of the waking day chewing, they found. Yet on average we chew for less than 10 per cent of the day, says Organ.
The pair then did a comparison of molar size and found that humans fall well outside the normal range for primates: we have small molars for our body size. When they included teeth from fossils of extinct hominins, the analysis revealed that Homo habilis and its contemporary H. rudolfensis fit well with the average for similarly sized primates. But Neanderthals and our direct ancestor, H. erectus, had small teeth for their body size.