In the Shadow of Man

In the 1950s, the scientific community had little knowledge about great apes, especially their behavior in the wild. Only one study of wild great ape communities had been attempted, and it had yielded few substantial results. This study was conducted by Henry W. Nissen, who spent two months in the forests of French Guinea, West Africa, studying the chimpanzees there. Scientists knew so little that they didn't understand that chimpanzees make and use tools. Therefore, most anthropologists’ definitions of humans included the notion that humans are the only tool-using species.

Louis Leakey felt that academic research into great apes in the wild would yield insights into the evolution and behavior of our shared ancestors. Leakey’s work focused on the excavation of hominid skeletal remains in East Africa, particularly the Olduvai Gorge. This work was of great interest to anthropologists, who understood that humans shared a common ancestor with other primates but had little detailed evidence to understand how different hominid species evolved. Leakey uncovered skeletal remains of the species Homo erectus and Paranthropus, which helped fill in the evolutionary human family tree.

Departing from the established way of engaging researchers, Leakey intentionally sought someone without formal training to conduct the chimpanzee study.