evidence: They concluded that humans likely were apex predators who ate mostly meat for around 2 million years, up until 12,000 years ago, when the last ice age ended. The review, published in 2021 in the American Journal of Biological Anthropology, argued that humans have more physiological similarities to carnivores than to herbivores, such as highly acidic stomachs to break down complex proteins and kill harmful bacteria, and the high body fat capable of carrying carnivores through a period of fasting before the next big kill. [...] But even if we were once apex predators with meat-heavy diets, that doesn't mean modern humans should ascend the trophic ladder, Ben-Dor told Live Science. "It doesn't necessarily follow that because we were carnivores in the past, we are today at the top of the food chain," he said. "However, our love for meat has everything to do with our Pleistocene carnivorous past."