I lay down on my camp bed, closed my eyes and, as always when I returned home at the end of the day, tried not to let my feelings overwhelm me. I arranged my day and my routine in such a manner as not to leave myself with much time alone and little to do, but his moment of the early evening, the light milky and orange, with the first bats jinking and swooping between the trees, and the tentative creek-creek of the crickets announcing the onset of dusk, always brought in its train a familiar melancholy and cafard and, in my particular case, an awful self-pity. I forced myself to sit up, took some deep breaths, inveighed powerfully against the name of John Clearwater, and went to sit at the little trestle desk where I worked. (p. 21)

Genetically, chimpanzees are the closest relatives to human beings. When...