Tropical Grass was the Main Human Diet 3.5 Million Years Ago

Many centuries ago, much before man ate meat and vegetables, the staple food was grass, a new study finds out.

The study, by researchers from Oxford University, says that our human ancestors living in Central Africa about 3.5 million years ago subsisted on tropical grasses and sedges mainly.

Julia Lee-Thorp, researcher at the University of Oxford and her team studied bones of Australopithecus bahrelghazali, an early hominine that lived in the savannah grasslands near Lake Chad in Africa. The team found high levels of carbon 13 in the bones, which is typical of animals with a rich grass diet.

"We found evidence suggesting that early hominines, in central Africa at least, ate a diet mainly comprised of tropical grasses and sedges. No African great apes, including chimpanzees, eat this type of food despite the fact it grows in abundance in tropical and subtropical regions," Lee-Thorp said, according to the Oxford University report.

"The only notable exception is the savannah baboon, which still forages for these types of plants today. We were surprised to discover that early hominines appear to have consumed more than even the baboons", Thorp added.

"The ancestral human diet diverged from that of the apes much sooner than previously thought", the Daily Mail reported. The older studies suggest it was about 2.8 million years ago.

"Our data show by about 3.5 million years ago A bahrelghazali was fully engaged in exploiting C4 biomass," Lee-Thorp said.

"The results imply australopithecines (early humans or hominids) had become broad generalists foraging opportunistically for locally abundant resources that included significant quantities of savannah resources, unlike chimps," said Lee-Thorp.

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