Hands evolved to punch faces. Faces evolved to take punches. That’s the hypothesis being bandied about by University of Utah researchers Michael Morgan and David Carrier, the pair proposing that the apparent “protective buttressing” of our skulls and hands is a sign of violent prehistoric fights where fists of fury dictated who would mate and who would exit the gene pool. It’s a great example of a just-so story.

Morgan and Carrier’s new paper, published in Biological Reviews, is a sequel to an initial paper that suggested our hands evolved as cudgels. This was more than a bit of a stretch. “The goal of this study was to test the hypothesis that the proportions of the