Jane Goodall Breaks Rules: Chimps Use Tools

A 26-year-old Englishwoman with no university degree sat in a Tanzanian forest on November 4, 1960, and watched a chimpanzee strip leaves from a twig, insert it into a termite mound, and extract insects to eat. Jane Goodall had just witnessed something the scientific establishment considered impossible: a non-human animal deliberately manufacturing a tool. When she telegrammed her mentor Louis Leakey, he famously replied, "Now we must redefine tool, redefine man, or accept chimpanzees as humans." Goodall had arrived at the Gombe Stream Reserve on the shores of Lake Tanganyika four months earlier, sent by Leakey, the renowned paleoanthropologist who believed long-term observation of great apes could illuminate early human behavior. The establishment was skeptical of her qualifications. She had worked as a secretary and waitress, and she committed what primatologists considered cardinal sins: naming her subjects rather than numbering them and describing their emotional states in human terms. The chimpanzee she observed was one she named David Greybeard, a male who became her primary subject and the first chimp to lose his fear of her presence. Over subsequent weeks, she observed David and others not merely using found objects as tools but modifying materials to create them, selecting specific stems and adjusting their length and flexibility for the task. The discovery forced a reassessment of what separated humans from other animals. Tool use had been considered the defining characteristic of the genus Homo since Benjamin Franklin described humans as "tool-making animals." Goodall's observation obliterated that boundary and opened a field of research into animal cognition that continues to expand. Her subsequent 60-year study at Gombe remains the longest continuous field study of any animal species, documenting warfare between chimpanzee groups and complex social hierarchies that blurred the line between human and animal with every passing decade.