Early humans had feet like ours and left lasting impressions in the form of 1.5 million-year-old footprints, some of which were made by feet that could wear a size 9 men's shoe.

The findings at a Northern Kenya site represent the oldest evidence of modern-human foot anatomy. They also help tell an ancestral story of humans who had fully transitioned from tree-dwellers to land walkers.

"In a sense, it's like putting flesh on the bones," said John Harris, an anthropologist with the Koobi Fora Field School of Rutgers University. "The prints are so well preserved ."

Almost human

Harris and other colleagues report in the Feb. 27 issue of the journal Science on finding several footprint trails within two sedimentary rock layers. An upper sedimentary layer included two trails of two prints each, one group of seven prints, and a variety of isolated prints. The lower layer had a trail of two prints and a single isolated print likely from a smaller, juvenile human.

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