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A new study has indicated that early human ancestors were walking on two legs about 7 million years ago.
Scientists at New York University in the US found new proof from bones showing that Sahelanthropus tchadensis walked on two legs, which backs up earlier studies. Sahelanthropus tchadensis is believed to be the oldest known human ancestor.
After the discovery of a skull bone and teeth in northern Chad, a country in Africa, in 2001, researchers concluded that this prehuman walked upright. In 2022, scientists from France and Chad presented their findings in the journal Nature, based on examinations of two forearm bones and one thigh bone.
The structure of the thigh bone indicated that the prehuman usually moved on two legs on the ground but also travelled in trees. It had a longer thigh bone than forearm.
