In the studies that have been done on primate and early human evolution, there is strong evidence that eating meat played a large role in increased brain size. Early plant eating hominids had a cranial capacity of about 300 cc to 500.cc. The earliest known meat eating hominids had a capacity of about 600 cc to 750 cc. Why the difference?
Hominids require amino acids in their diets to remain healthy. It is difficult to find them in vegetation that is easily digestable. Thus, the hominids had to come up with a solution. The solution was to add meat to their diet. The early hominids were small creatures without tools for hunting animals. How were they going to get the meat they needed?
Leopards were mighty hunters that lived in the same area as the hominids. Many times the leopards made a kill and either didn't eat or didn't eat all of the animal, so they would store the meat for later. If a hominid could recognize the opportunity, and was quick enough, this provided a great chance for him to get some meat. The hominid had to be able to read the signs to find the meat and know when it was safe to get the food. The men were the primary scavengers for meat, but the women also played their part. They gathered vegetables and fruits and traded these for some of the meat from the males. The females had to be intelligent enough to have a place in mind to bring the food and forethought to have a way to transport all the food they gathered. All of this required thought, which exercised the brain, helping to form new connections, and ultimately encouraging brain growth. The increased brain size made planning easier, so the creatures with the larger brains got meat more and were healthier. This led to the natural selection of the animals with bigger brains. Meat eating animals do not have to eat as frequently as animals who rely solely on vegetation. This means that the meat eating hominids had more