selection could operate, and that what is important about it is the observation that the adult chimpanzee was behaving as if it recognized the infant’s lack of understanding.

One of the ways in which social learning has been demonstrated for chimpanzees (Whiten and Boesch 2001) and orangutans (van Schaik et al. 2003) is in identifying the differences between groups, while holding other variables equal. There is still a question of the scale at which genetic constraints might be operating (assuming genetic variation between the studied groups is enough to separate them whatever the variation within groups; see Gagneaux et al. 2001), and there seems to be a role for some ecological constraints. The problem seems to be very difficult (Laland and Janik 2006), but there is at least an argument that for chimpanzees many of the supposedly cultural differences reflect genetic differences between populations (Langergraber et al. 2011) or geographic ones (Kamilar and Marshack 2012). One implication of these studies would be an expectation that as culture-bearing organisms moved apart the genetics of populations differentiated by drift and as their geographic circumstances became distinctive their socially learned behavior might also have shown differences.

Among humans, it may be problematic whether there is good evidence for social learning in some domains (Whiten et al. 2003), but there are other situations where the extent of social learning is undeniable and very strong. Two important cases of such social learning are language and aspects of ritual behavior, and for these there is no doubt that learning is social and there is absolutely no parallel in non-humans. To suggest otherwise is to misunderstand the nature of social learning in humans, and failure to be clear about the nature of such social learning is a major contributor to the confusion about whether it is present in non-humans. In all cases, language is the usual means of communication among humans and only present among other free-living animal species by stretching the definitions of language (see, for example, extensive discussions in Davidson 1999). As for ritual, in many cases recognition of membership of societies derives from performance of rituals such as rites de passage by which the relationships of individuals to other members of society are determined (see, for example, Rappaport 1999). This is not to suggest that social learning can only be identified through ritual, but that if ritual can be identified then social learning must have taken place. There seems to be no evidence of ritual or other social practices among non-human primates. The practice can be identified in archaeological evidence (Ross and Davidson 2006). In other words, social learning is manifest in human societies in these and other ways which fundamentally affect the human-based criteria for recognition of culture, but which will always be distinct from learning in other animals. Some primatologists might say we just do not know about such things, but in our heart of hearts, we know non-human primates do not have such learning.

Among humans, the SOH doctrine that Arnold was expressing was about the application of the word “culture” only to what he could see of his own culture. This usage has a long history among people who have not interacted with other cultures, and the definition of SOH culture is about a special, privileged section of “our” own society (people who think of themselves as the best). What is generally missing from such definitions is the different perception of privilege in different sections of society – the language-based symbolic recognition of differences in value. From these different sections, what is seen as “best” can vary even within what would otherwise be considered one society (Bach versus the Beatles; Botticelli versus Banksy). Clearly there is ethnocentrism and other sorts of special pleading about such definitions. What is important here is that these vernacular understandings of the word “culture” are part of the reason why so many scientists have, historically, preferred not to use the word or its related concepts at all.

This variable meaning of culture can be expressed in a simple diagram (Fig. 10.1). Here, within the field of all learned behavior (which I will call Culture-L, C-L), there are much smaller areas which represent the learned behavior in a particular society or community (Culture-C, C-C). Within that, a small portion represents Arnold’s “best” (Culture-SOH, C-SOH). For another society, there will be differences in what is learned, but for some societies, there will also be overlap. Differences at the level of what is learned may be a result of no more than different practice with no particular assessment on the part of the learners that one thing is better than another. However, giving importance to the “best” portion of what is learned is often a way in which one society distinguishes itself from another (Opera versus Grand Ole Opry). As this process of evaluation of cultural knowledge emerged during the evolution of human society, there arose the potential for rapid diversification of cultures. The presence of such diversification, therefore, could be said to be a result of the evaluation of the quality of what is learned – making the multi-millennial monotony of the Acheulean an unlikely candidate for such evaluation. It is a question that cannot be dealt with here, whether such evaluations could only have taken place in societies that had language.

Culture and Material Culture

Faced with the invisibility of the social and ontogenetic processes that make culture possible, and despite the certainty of the evolution of ontogeny due to changes in life history (Locke and Bogin 2006; Nowell 2010), archaeologists and primatologists have both appealed to characteristics of material culture to identify aspects of culture, as McGrew did (McGrew and Tutin 1978; McGrew 1992). The method

is full of pitfalls, but does return the emphasis to what archaeology is good at: material things. Here I will attempt to concentrate the discussion not only on the thing itself but on the social and learning processes that must have operated to achieve the qualities of such things.

One of the features of the list of behaviors deemed to be cultural (C-L) among chimpanzees is the large number that seem to involve materials removed from their fixed position (e.g., sticks broken off trees) on which actions are performed: 29 of the 39 (74.4 %) of the behaviors in the authors’ group D (Whiten et al. 1999), as well as 12 out of 19 (63.2 %) among orangutans (van Schaik and Pradhan 2003). One measure of the cultural difference between humans and other apes is that, among humans, it is impossible to quantify the numbers or proportions of material objects that are removed from their fixed positions because there are just so many of them. Whatever the qualitative differences between the learned behaviors of humans and other animals there are huge quantitative differences, too. Clearly one of the things we can look towards is trying to understand the ways in which hominins modified their environments through cultural constructions in this physical way.

Production of stone tools first required procurement of tool stone raw material (which became a core) and of hammer stone. Some aspects of procurement are similar to those for other primates (especially chimpanzees; see Wynn and McGrew 1989; Wynn et al. 2011). Among chimpanzees at most times, most raw materials are at hand to secure for their elementary technology. Literally, they arrive at a termite mound and reach out and pluck vegetation to make into a probe (Goodall 1986). Sometimes they pluck lots of pieces of raw material (thus indicating foresight?) when at least tens of metres away from the use site (thus indicating planning?)

(Bill McGrew personal communication, December 2003). It is well-documented that chimpanzees carry stones for nutcracking from the last used nutting tree to a new nutting tree as it becomes useful, as shown by keeping track of where stones circulate (Boesch and Boesch 1984a, b). This can amount to another order of magnitude greater in terms of transport distance. The knapped stones from the 2.34 Ma site of Lokalalei were removed from sources said to be “available close to the site”, although some cores seem to have been carried to the site already prepared (Delagnes and Roche 2005). This selection of raw materials close to the site seems to have been a consistent pattern for early sites (Goldman-Neuman and Hovers 2012) but shortly after 2 Ma, at Oldupai2 Gorge, raw materials were deposited several kilometers from their source (Hay 1976).

Tool stone raw materials have the advantage that they are connected to their source by petrology. A large amount of data has now accumulated showing the distances over which raw materials travelled at different times. Often this is difficult to interpret, but some general principles can be established. One study collected various estimates and sought to relate it to the network sizes and hence the communicative abilities at particular time periods (Marwick 2003, using data from Féblot-Augustins 1997; Roebroeks et al. 1988, and others). For most regions and periods, there was a commonest distance which was very short – raw materials were acquired relatively locally; there was a group of raw materials from distances not too far from the most abundant source and this group often had an upper limit of distance that was separated from more distant sources; and

2The archaeologically well-known name Olduvai has recently been shown to have been a corruption of the original Maasai name Oldupai.

there were small amounts of raw materials that were transferred relatively larger distances. Figure 10.2 plots these distances against time (using the mean of the time intervals in Marwick’s data).

The important point here is that, in Marwick’s study, the distances from which the bulk of the tool stone was acquired remained small until late in prehistory (the data Marwick plotted were described as “Late Middle Palaeolithic and early Upper Palaeolithic”, say about 50 thousand years ago).

Cultural artifacts acquire meaning first as indexical signs

– they are consistently associated with particular situations or conditions. Thus, the debris left from flaking episodes could be seen by the knapper or by other hominins as a sign that knapping had taken place there previously (Davidson and McGrew 2005). At some indeterminate time later, such signs came to be seen as symbols of identity through comparison of people in those situations or conditions (the case for this is often made by analogy with the situation among modern people of the Kalahari described by Wiessner 1983, but the analogy cannot tell us anything about the timing of that appearance). Such a possibility has been explored for Acheulean sites (Pope et al. 2006). There is nothing like this process of transformation of index into symbol in the non-human world, and it is arguable that it has not even been demonstrated that non-humans comprehend created indexes (but see one such claim by Savage-Rumbaugh et al. 1996). Such cultural artifacts that can function, to third parties, as markers of group identity, do not seem to be in the same category as the common practices in food-getting and tool use among non-human primates. The most well-known apparent exception to this, the chimpanzee hand-clasp (McGrew and Tutin 1978), is not an artifact and there is little evidence that it functions as a sign to third parties (other

than primatologists). One of the central challenges in applying the concept of culture to any group other than modern humans is how the use of symbols first occurred, and then transformed culture (for a related argument about the origins of pictures, see Davidson 2012).

Culture in Non-human Animals

and Evolution

When McGrew (1992) argued for culture in the material products of chimpanzees, apes and early hominins were much less well-known. It was straightforward to argue that this level of culture would be a feature of the last common ancestor of chimpanzees and humans. A similar argument had been put forward previously (Isaac 1978) and many times before and since (e.g., Noble and Davidson 1996). But when similar claims were made for orangutans (van Schaik et al. 2003) problems emerged: was there culture (C-L) in the last common ancestor of chimpanzees and orangutans? Is there, for example, any evidence for it among Ramapithecines (because orangutans, unlike chimpanzees, seem to have fossil ancestors) (Lipson and Pilbeam 1982; Prasad 1982). If we are looking at an LCA with orangutans, what about the question of culture in bonobos and gorillas (see the phylogenetic tree in Fig. 10.3)? The bonobo question is now settled (Hohmann and Fruth 2003; Savage-Rumbaugh et al. 2004), but something needs to be said about gorillas3. If they do not

3Since this paper went to the publisher, tool use for food acquisition has been reported (Kinani and Zimmerman 2014) among free-living mountain gorillas.