Early human ancestors, who lived in central Africa 3.5 million years ago, ate a diet mainly comprised of tropical grasses and sedges, a new research has revealed.
The study also suggest that humans began eating grass half a million years earlier than thought, soon after they started leaving the trees.
Julia Lee-Thorp at the University of Oxford and her colleagues found high levels of carbon-13 in the bones of Australopithecus bahrelghazali, an early hominin that lived on savannahs near Lake Chad in Africa
According to New Scientist, Lee-Thorp said the finding is the earliest evidence of eating savannah plants
Previously, the oldest evidence of grass-eating was from 2.8 million years ago.
The researchers suggested that A. bahrelghazali might have eaten roots and tubers, rather than tough grass blades.
Adding these to their diet may have helped them leave their ancestral home in east Africa for Lake Chad, they said.