The body is absurd. The sounds, smells, textures, impulses, tics, blemishes, engorgements, excretions of our organs—these make up the outrageous conditions of our animal existence, from infancy to old age. We suffer the daily indignities, surprises, and wonders of the flesh because we are stuck with this imperfect vessel. No wonder we make so many dick jokes.

In Why is the Penis Shaped Like That? And Other Reflections On Being Human, research psychologist and science writer Jesse Bering aims to understand the function of human attributes through the lens of evolutionary psychology. In considering