Hmm, I'll go find a source, but I've heard it all over the place. The reason we could develop such large brains is because our masseter muscles have gotten much, much smaller. It used to be, (and this is hundreds of thousands of years ago, before homo sapiens existed as a distinct species), we had to spend hours upon hours chewing our food- this required Massive masseter muscles & a robust jaw, which in turn needed to be seated in a sturdy skull. Which, in turn, precluded large brain sizes.
Cooking the food on the other hand made it easier to digest, saving us energy in our gut & providing more available nutrients/calories, which helped out with our energy-hungry brain.
-watching a long-ass presentation on it now, I'll see if I can report back in about an hour.
Well, the video was a bust, but I do have some notes and a less 'impressive' kind of source that states what I was looking for.
Here's the source:
http://www.livescience.com/24875-meat-human-brain.htmlHere's the video;
https://www.youtube.com/watch?v=69ckWLrvVhgAnd some recommended spots:
15:00 is where he starts the presentation proper
25:00 he started his presentation on effects of cooking on food
32:00 is some nice data on protein
46:00 is some data I had in my head.
I quit at 47:00 because his bit on biological adaptations took up all of 2 minutes, half of which was presentation fluff.
If you really want me to, I can go access my college's subscription to proquest and look through scholarly journals and whatnot. But fuck that.