Tropical Plants Were Our Early Ancestors' Staple Diet

According to a new study, researchers found evidence that our very early ancestors survived on tropical plants.

Researchers from Oxford University have found evidence that approximately 3.5 million years ago; the staple diet of our very early ancestors in central Africa consisted mainly of tropical grasses and sedges.

"We found evidence suggesting that early hominins, in central Africa at least, ate a diet mainly composed of tropical grasses and sedges," Professor Lee-Thorp, a specialist in isotopic analyses of fossil tooth enamel, from the Research Laboratory for Archaeology and the History of Art, said. "No African great apes, including chimpanzees, eat this type of food despite the fact it grows in abundance in tropical and subtropical regions. The only notable exception is the savannah baboon which still forages for these types of plants today. We were surprised to discover that early hominins appear to have consumed more than even the baboons."

According to researchers, the findings of this study proves how there has been a change in diet even with early hominins.

"The finding is significant in signaling how early humans were able to survive in open landscapes with few trees, rather than sticking only to types of terrain containing many trees. This allowed them to move out of the earliest ancestral forests or denser woodlands, and occupy and exploit new environments much farther afield," said the study.

"Based on our carbon isotope data we can't exclude the possibility that the hominins' diets may have included animals that in turn ate the tropical grasses," Lee-Thorp said. "But as neither humans nor other primates have diets rich in animal food, and of course the hominins are not equipped as carnivores are with sharp teeth, we can assume that they ate the tropical grasses and the sedges directly."

The findings of the study are published in the online edition of Proceedings of the National Academy of Sciences.