Bipedal trackways discovered in 1978 at Laetoli site G, Tanzania, and dated to 3.66 million years ago are widely accepted as the oldest unequivocal evidence of obligate bipedalism in the human lineage. Another trackway discovered in 1976 at nearby Laetoli site A was partially excavated and attributed to a hominin, but curious affinities with bears marginalized its importance to the paleoanthropological community. In new research, paleoanthropologists...
