Human beings were always defined as the “tool-maker species.” But our domination over this important skill was brought into question in the 1960s when renowned anthropologist Jane Goodall discovered that chimpanzees will pick and modify stems of grass in order to use them to collect termites. Her findings challenged Homo sapiens’ very place in the biological order. Since Dr. Goodall’s research, scientists’ knowledge of tool use by animals has expanded exponentially. We now know that monkeys, crows, parrots, pigs, and many other animals can use tools, and research on animal tool use has changed our understanding of how...