Patterns of coalition formation and spatial association in a social carnivore, the African wild dog (Lycaon pictus)

Abstract

In many social species, relationships within groups seem to be non-random but related to variables such as rank, kinship or sexual attractiveness. The endangered African wild dog Lycaon pictus is a social carnivore that lives in large, stable packs, and intra-pack associations might be expected to display similar patterns. We investigated patterns of coalition formation (support during dominance interactions, and partnership interactions) and resting associations between members of a captive pack of 19 wild dogs. The social organization of the captive pack was similar to that of free-ranging packs in many respects. Polyadic (group) incidents of coalition support were also observed in a free-ranging pack. Patterns of coalition formation in the captive pack were related to rank. Most aggressive interactions involved high-ranking individuals (particularly the alpha, beta and third-ranking males) and coalitionary support tended to reinforce the existing hierarchy. However, there was at least one example of support influencing a successful rank challenge. Support was affected by potential risks and benefits, the latter including dominance through association and revolutionary alliances. An even stronger pattern overlaid associations between pack members: coalitions and resting associations were strongest between members of the same age-sex cohort, and may have enabled the eventual dominance of younger pack members over adults. Among adults, coalitionary associations were sometimes overridden by intersexual relationships. The results from this captive pack suggest that wild dogs are sensitive to differences in competitive ability. This information, in conjunction with strong affiliative bonds between littermates, is used to manoeuvre for position in the social hierarchy. It may also be important during dispersal, in encounters with other dispersing groups of the same sex. Although most features of the social structure of the captive pack were comparable to those of free-ranging packs, aspects such as the influence of relatedness on coalition formation still need to be explored.

Coalitions in theory and reality: a review of pertinent variables and processes

“…Another study using a Bayesian approach provided strong evidence that alpha male turnover would not have occurred in the absence of coalitions in three populations of chimpanzees (Hasegawa & Kutsukake, in press). Outside the primates, one study reported that the beta and gamma males exchanged coalitionary support in African wild dogs (de Villiers et al, 2003). It was inferred that this revolutionary alliance may have enabled the beta and gamma males to overthrow the alpha male.…”

“…Age effects are not restricted to primates, but have also been documented in other mammals. For example, in a captive group of wild dogs, members of the same age cohort supported each other more than individuals of dissimilar ages (de Villiers et al, 2003). In addition to reinforcing the existing dominance hierarchy, male age-mates may have another important reason to form coalitions when they disperse together and attempt to establish their own breeding groups (de Villiers et al, 2003).…”

“…For example, in a captive group of wild dogs, members of the same age cohort supported each other more than individuals of dissimilar ages (de Villiers et al, 2003). In addition to reinforcing the existing dominance hierarchy, male age-mates may have another important reason to form coalitions when they disperse together and attempt to establish their own breeding groups (de Villiers et al, 2003). An important consequence of this age-dependence of participation in coalitions is that the demographic structure of a group can act as an important constraint on behaviour (Chapais & Schulman, 1980;Barrett & Henzi, 2002;Mitani et al, 2002;Bissonnette, 2009).…”

Modelling Dominance Hierarchies Under Winner and Loser Effects

“…Of course it should be noted that many real populations are more complex, with group membership in a state of flux, or coalitions between group-mates (e.g. close relatives) ( [14], [46]), and so often our idealised conditions will not apply.…”

Conflict over the timing of breeder replacement in vertebrate and invertebrate societies

“…However, helpers offspring are less likely to survive to one year of age than the breeders offspring are and breeder females have been observed to kill helpers pups (Girman et al, 1997). Although the overall level of successful helper reproduction is unclear it is likely that at least some helpers have direct reproduction in the presence of a dominant breeder (Frame et al, 1979;Creel et al, 1997;Girman et al, 1997;de Villiers et al, 2003).…”