In October 1960, at Gombe Stream in Tanzania, Jane Goodall watched a chimpanzee she named David Greybeard strip the leaves from a stem of grass and poke it into a termite mound, then withdraw it coated with clinging termites to eat. Until that moment, tool making — not just tool use — was treated as a defining, uniquely human trait. Goodall's mentor Louis Leakey cabled back: "Now we must redefine tool, redefine man, or accept chimpanzees as human."
Decades of follow-up fieldwork across African chimpanzee populations found that different communities use different tool kits — termite-fishing sticks, nut-cracking stones, leaf sponges — passed down socially rather than genetically, giving primatologists their strongest case yet for non-human culture.
A chimpanzee strips a grass stem, fishes it into a Gombe termite mound, and withdraws it coated with termites to eat — while a juvenile nearby watches and gradually picks up the technique.
Dip success depends on real variables from Goodall's field notes: stem length, whether leaves are stripped off (true tool making), and termite activity by season. A juvenile's own success rate climbs the more it observes — a simple model of cultural transmission.
Adjust tool length, toggle leaf-stripping and season, and watch the dip success rate change live. Enable social learning to see the juvenile's skill — and its own harvests — grow purely from watching the adult.
Goodall's 1960 observation of David Greybeard forced primatologist Louis Leakey to write: "Now we must redefine tool, redefine man, or accept chimpanzees as human" — permanently changing how science defines tool use.