At Olduvai Gorge, where excavations helped to confirm Africa was the cradle of humanity, scientists now find the landscape once fluctuated rapidly, likely guiding early human evolution.These findings suggest that key mental developments within the human lineage may have been linked with a highly variable environment, researchers added.

Olduvai Gorge is a ravine cut into the eastern margin of the Serengeti Plain in northern Tanzania that holds fossils of hominins — members of the human lineage. Excavations at Olduvai Gorge by Louis and Mary Leakey in the mid-1950s helped to establish the African origin of humanity.

The Great Drying?

To learn more about the roots of humanity, scientists analyzed samples of leaf waxes preserved in lake sediments at Olduvai Gorge, identifying which plants dominated the local environment around 2 million years ago. This was about when Homo erectus, a direct ancestor of modern humans who used relatively advanced stone tools, appeared.

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