Carnivorism & the Evolution of the Human Brain

Just read over "An Open Letter to the Times Editor" (8Dyay8D's follow-up on her article "Vegetarianism")

She got me thinking... about diets, and as I read over her opening statement (as quoted below). I went to look up some facts, and learned a lot more.

"When you say "big brains" do you mean fat?? Or smart??" Did you know the brain is roughly two-thirds fat? And that scientists have discovered that an integral key to the evolution of the human brain is due to our (or rather, our extremely distant) ancestors' consumption of meat?

These scientists determined that certain types of early humans had greater intelligence than that of others. They also discovered that docoahexaenoic acid (DHA) is a large contributor to brain growth, and that seafood had large quantities of DHA in it. Finally, they came to the conclusion that early humans who lived by water and whose diets were largely composed of seafood experienced this brain growth, while other inland early humans (such as Australopithecines) did not. (Australopithecines had a brain about the size of a chimpanzee's for 3 million years.)

While I realize that it depends on your perception of "vegetarianism" as to whether or not seafood fits your dietary regime... I still found it intriguing that if it weren't for meat, humans might not be as advanced as we are. And although we can get all our nutrients from pills, vitamins and our processed "energy" foods, we are so far unable to fully determine the long-term effects of these processed "miracle foods."

For all we know, by not eating meat, and supplementing them with "alternatives," we could be inadvertently missing a key unknown enzyme or amino-acid that could inhibit or postpone the evolution of humans.