Abstract: Decades-long field research has flowered into integrative studies that, together with experimental evidence for the requisite social learning capacities, have indicated a reliance on multiple traditions ('cultures') in a small number of species. It is increasingly evident that there is great variation in manifestations of social learning, tradition and culture among species, offering much scope for evolutionary analysis. Social learning has been identified in a range of vertebrate and invertebrate species, yet sustained traditions appear rarer, and the multiple traditions we call cultures are rarer still. Here, we examine relationships between this variation and both social intelligence-sophisticated information processing adapted to the social domain-and encephalization. First, we consider whether culture offers one particular confirmation of the social ('Machiavellian') intelligence hypothesis that certain kinds of social life (here, culture) select for intelligence: 'you need to be smart to sustain culture'. Phylogenetic comparisons, particularly focusing on our own study animals, the great apes, support this, but we also highlight some paradoxes in a broader taxonomic survey. Second, we use intraspecific variation to address the converse hypothesis that 'culture makes you smart', concluding that recent evidence for both chimpanzees and orang-utans support this proposition.

Abstract: Wild chimpanzees (Pan troglodytes) have a rich cultural repertoire--traditions common in some communities are not present in others. The majority of reports describe functional, material traditions, such as tool use. Arbitrary conventions have received far less attention. In the same way that observations of material culture in wild apes led to experiments to confirm social transmission and identify underlying learning mechanisms, experiments investigating how arbitrary habits or conventions arise and spread within a group are also required. The few relevant experimental studies reported thus far have relied on cross-species (i.e. human-ape) interaction offering limited ecological validity, and no study has successfully generated a tradition not involving tool use in an established group. We seeded one of two rewarded alternative endpoints to a complex sequence of behaviour in each of two chimpanzee groups. Each sequence spread in the group in which it was seeded, with many individuals unambiguously adopting the sequence demonstrated by a group member. In one group, the alternative sequence was discovered by a low ranking female, but was not learned by others. Since the action-sequences lacked meaning before the experiment and had no logical connection with reward, chimpanzees must have extracted both the form and benefits of these sequences through observation of others.

Abstract: Self-directed behaviour (SDB) can be used as a behavioural indicator of stress and anxiety in nonhuman primates (Maestripieri et al. 1992, Animal Behaviour, 44, 967-979). We investigated the effect of nearest neighbours' relative dominance status on the SDB of sexually mature female olive baboons, Papio anubis. When the animal nearest to (within 5 m of) a female was a dominant individual, SDB rates (a combined measure of self-scratching, self-grooming, self-touching, body shaking and yawning) increased by ca. 40% over those observed when the nearest neighbour was a subordinate. The results indicate that (1) SDB can be used as a measure of uncertainty during the social interactions of cercopithecine primates and (2) as there was considerable variation in SDB response according to the nature of the dominant individual, SDB can be used to assess relationship security (i.e. the perceived predictability of a relationship for one partner). Finally, in combination with measures of affiliation rate, SDB may provide insight into relationship value.

Abstract: Abstract. Competition for food is thought to play a key role in the social organization of group-living female primates, leading to the prediction that individual foraging success will be partly regulated by dominance relationships. Among adult females in a group of free-ranging olive baboons, dominance rank was significantly correlated with nutrient acquisition rates (feeding rates and daily intakes), but not with dietary diversity or quality, nor with activity budgets. The mean daily food intake of the three highest-ranking females was 30% greater than that of the three lowest-ranking females, providing an explanation for relationships between female rank and fertility found in a number of other studies of group-living primates. The intensity of feeding competition, as measured by supplant rates and spatial clustering of individuals, increased during the dry season, a period of low food availability, seemingly because foods eaten then were more clumped in distribution than those eaten in the wet season. Implications for models of female social structure and maximum group size are discussed.

Abstract: ABSTRACT Tactical deception occurs when an individual is able to use an “honest” act from his normal repertoire in a different context to mislead familiar individuals. Although primates have a reputation for social skill, most primate groups are so intimate that any deception is likely to be subtle and infrequent. Published records are sparse and often anecdotal. We have solicited new records from many primatologists and searched for repeating patterns. This has revealed several different forms of deceptive tactic, which we classify in terms of the function they perform. For each class, we sketch the features of another individual's state of mind that an individual acting with deceptive intent must be able to represent, thus acting as a “natural psychologist.” Our analysis will sharpen attention to apparent taxonomic differences. Before these findings can be generalized, however, behavioral scientists must agree on some fundamental methodological and theoretical questions in the study of the evolution of social cognition.