STONE TOOLS AND THE UNIQUENESS OF HUMAN CULTURE

There is growing evidence that some species other than the human have behaviour that should be called cultural. Questions arise, then, of how human (and, perhaps, ape) cultures are different from those of other animals and how they have become so different. Human cultures are creative, generating new patterns of behaviour from those learned from others. Stone tool making provided a niche for the recruitment of tools and tool-making processes from one function to another. This is something not yet recorded for apes. This article explores the possible role of stone tools in the emergence of this creativity.     

Behavioral diversity in populations of free-ranging chimpanzees in Africa: is it culture?

Behavioral differences exist among populations of wild chimpanzees (Pan troglodytes, Hominoidea) across Africa. Deciding if these are cross-cultural differences demands careful interpretation and rigorous scrutiny. Even standard patterns like social grooming may show variation in detail between neighboring populations. Some patterns of tool use, such as using hammers to crack nuts, also vary across far western Africa. At least 37 populations of free-ranging chimpanzees show tool use, and 14 show at least one habitual pattern of tool use. Regional differences exist among the three subspecies or geographical races of chimpanzees. Convincing empirical demonstration of social customs and traditions in non-human species is problematical, and even something so simple in principle as innovation is hard to show in practice. However, culture need not depend on imitation, teaching, or language, either in humans or in other species.     

Cumulative culture in nonhumans: overlooked findings from Japanese monkeys?

Cumulative culture, generally known as the increasing complexity or efficiency of cultural behaviors additively transmitted over successive generations, has been emphasized as a hallmark of human evolution. Recently, reviews of candidates for cumulative culture in nonhuman species have claimed that only humans have cumulative culture. Here, we aim to scrutinize this claim, using current criteria for cumulative culture to re-evaluate overlooked qualitative but longitudinal data from a nonhuman primate, the Japanese monkey (Macaca fuscata). We review over 60 years of Japanese ethnography of Koshima monkeys, which indicate that food-washing behaviors (e.g., of sweet potato tubers and wheat grains) seem to have increased in complexity and efficiency over time. Our reassessment of the Koshima ethnography is preliminary and nonquantitative, but it raises the possibility that cumulative culture, at least in a simple form, occurs spontaneously and adaptively in other primates and nonhumans in nature.     

Disappearance rate of chimpanzee scats: Implications for census work on Pan troglodytes

Scat (faeces) decay rate estimates are used to calculate animal species abundance and density. For African great apes, this has been measured only for Gorilla; chimpanzee scats are assumed to decay at a faster rate due to lower fibre content. We provide the first systematic measure of scat decay rate duration for Pan troglodytes schweinfurthii, in Kanyawara, Kibale National Park, Uganda. We used two methods: (1) multiple visits to obtain prospective decay rates (PDR) (N = 96 scats) and (2) a novel approach of time‐lapse photography (TLP) (N = 17 scats). Most of the visited scats (67%) decayed in ≤24 hr, and median decay rate duration from photographic documentation was 18 hr. Using regression analyses, we tested 11 covariables to determine predictors for decay rate duration. Greater volume of scat and reduced levels of diurnal dung beetle activity were positively associated with longer decay rate duration. Given a high prevalence of dung beetle activity (88% of scats), particularly within 3 hr post‐defaecation, we suggest the use of the alternative term, disappearance rate of scats. With a rapid disappearance rate, scat count surveys of unhabituated chimpanzees are challenging; further work is then needed for Pan spp. to determine spatial and temporal differences at intra‐ and inter‐species level.     

Termite fauna related to differences in tool-use between groups of chimpanzees (Pan troglodytes)

Nishida andUehara have contrasted two groups of chimpanzees at the Mahale Mountains in their manner of obtaining termites for food. K-group very rarely used tools, but evidence suggested that B-group did so regularly to fish forMacrotermes. They suggested that this difference was not a cultural one, but was explained by the absence ofMacrotermes in K-group's range. We attempted to test this hypothesis, and here examine the termite fauna in the ranges of the two groups. Our data confirm that termite-fishing was contingent upon the presence ofMacrotermes in B-group's range, and that cultural explanations are not necessary to explain the rarity of tool use by K-group, which instead could catchPseudacanthotermes without using tools. Comparison of the termite faunas in the ranges of K-group, of B-group, and of the chimpanzees at Gombe, suggest that, apart fromMacrotermes, two genera might be the main alternative prey:Pseudacanthotermes, which could be more commonly included in the diet at Gombe, and might also be eaten by B-group, andCubitermes which is available at both these sites.