Scientists uncover 24-million-year record of vegetation trends in East Africa. Findings lend weight to the idea that we developed key traits, flexible diets, large brains, complex social structures and the ability to walk and run on two legs, while adapting to the spread of open grasslands.

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Scientists uncover 24-million-year record of vegetation trends in East Africa. Findings lend weight to the idea that we developed key traits, flexible diets, large brains, complex social structures and the ability to walk and run on two legs, while adapting to the spread of open grasslands.