CAMBRIDGE, MASSACHUSETTS—Evolutionary biologist Daniel Lieberman of Harvard University and an international team of researchers suggest that the thick calluses that develop on the feet of people who go barefoot most of the time provide protection from pain without impeding sensory perception. According to a Science News report, the team members measured the thickness of calluses on the feet of 81 adults who live in cities and rural areas in western Kenya and either wear shoes all the time, little of the time, or none of the time. The researchers then used a device to poke the soles of the participants’ feet. The participants, in turn, were given a button to press to signal when they first felt pressure. “People who had thicker calluses had no loss of sensitivity,” Lieberman said, and our calloused, barefoot ancestors would have been able to sense the ground under their feet, he explained. For more on archaeology in Kenya, go to “Nomadic Necropolis.”