The work is based on bones and artifacts from a prehistoric “kitchen” that make up the earliest evidence that humans ate aquatic animals.
Stone tools and the butchered bones of turtles, crocodiles, and fish were found at the 1.95-million-year-old site in northern Kenya. No human bones were found, but the combination of remains suggests early humans used the site specifically to prepare meals.
According to the study authors, the addition of water-based prey into early-human diets may have been what boosted brain size in certain hominins—humans plus human ancestral species and their close evolutionary relatives.
That’s because reptiles and fish are particularly rich in long-chain polyunsaturated fatty acids. Some experts think this so-called good fat was “part of the package” of human brain evolution, said study leader David Braun, an archaeologist at the University of Cape Town in South Africa.
Discovering evidence for “brain food” in the late Pliocene (about 3 to 1.8 million years ago) may explain how bigger brains—for instance in our likely direct ancestor Homo erectus—arose in humans and their relatives about 1.8 million years ago, Braun said.