Meat has played a starring role in the evolution of the human diet

 Meat has played a starring role in the evolution of the human diet

 Raymond Dart, who in 1924 discovered the first fossil of a human ancestor in Africa, popularized the image of our early ancestors hunting meat to survive on the African savanna. Writing in the 1950s, he described those humans as “carnivorous creatures, that seized living quarries by violence, battered them to death … slaking their ravenous thirst with the hot blood of victims and greedily devouring livid writhing flesh.”

Eating meat is thought by some scientists to have been crucial to the evolution of our ancestors’ larger brains about two million years ago. By starting to eat calorie-dense meat and marrow instead of the low-quality plant diet of apes, our direct ancestor, Homo erectus, took in enough extra energy at each meal to help fuel a bigger brain. Digesting a higher quality diet and less bulky plant fiber would have

 allowed these humans to have much smaller guts. The energy freed up as a result of smaller guts could be used by the greedy brain, according to Leslie Aiello, who first proposed the idea with paleoanthropologist Peter Wheeler. The brain requires 20 percent of a human’s energy when resting; by comparison, an ape’s brain requires only 8 percent. This means that from the time of H. erectus, the human body has depended on a diet of energy-dense food—especially meat.