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A new analysis reveals clues about when primates started walking on two feet

By Nell Greenfieldboyce
Published January 2, 2026 at 2:32 PM MST

A big difference between humans and other apes is the ability to stride easily on two feet. A new analysis of fossil bones shows that adaptations for bipedal walking go back 7 million years.

Copyright 2026 NPR
Nell Greenfieldboyce
Nell Greenfieldboyce is a NPR science correspondent.
See stories by Nell Greenfieldboyce