tyb
The brain is the uppermost evolved spinal marrow. Its evolution and the intelligence thereof came from proteins from hunting game.
Also Our digestion system - including our teeth - show many indicators that meat is a part of humans diet in combination with vegetables and fruits.
Yummy bacon /w minerals - minerals which could only be compensated for with nuts that amount ten times or more in weight.
My educated opinion (from gastronomic proffession in high end)