Chimps prize animal flesh. The association of increasing brain size with animal food consumption. For many readers, the preceding paragraph is a convincing argument. This hypothesis, and the related research discussed in section 4 herein, suggest that the consumption of meat and the evolution of intelligence are closely interrelated. To summarize, the evidence of evolution is as follows.
Individual intelligence makes the final decision.
That is an example of the power of human intelligence, acting at the individual or personal level. It is appropriate to remind readers of some important points here. Survival is amoral. The moral arguments for vegetarianism are irrelevant in an evolutionary context. Individual intelligence implies individual choice.