Cataloguing tool-kits

By the early 1970s it was clear that wild chimpanzees at various sites in Africa had different repertoires of tool-use. By then the negative evidence from Gombe's well-known subjects could be set against the scrappy positive evidence from elsewhere. Put another way, if the toolkit of a group is defined as its complete set of tools and their use, then nothing has been added at Gombe since the early publications of Goodall (1964, 1968, 1973). Thus, from 1973 it could be said confidently that Gombe's apes did not use hammer-stones, and so a real difference existed between them and the chimpanzees of Cape Palmas, who were the subjects of the first anecdotal report of tool-use almost 150 years ago (Savage & Wyman, 1844).

Goodall (1973) produced the first catalogue of tool-use by free-ranging chimpanzees; it included 10 sites, and all but Gombe's data were based on short-term studies or single sightings (see Figure 8.1). Teleki (1974) followed with a list of 12 sites, of which only five were common to Goodall's catalogue of a year earlier! The most extensive published catalogue is that of Beck (1980), who compiled findings from 20 sites across Africa. More recently, Goodall (1986) produced another list, but this had only 16 populations of wild (but not released and free-ranging) chimpanzees. All of the previous efforts are now dated.

Table 8.1 lists 32 populations or groups of free-ranging chimpanzees in Africa that have shown some kind of tool-use, if a tool is defined as a ‘moveable, inanimate object used to facilitate acquisition of a goal’ (McGrew et al., 1975).