The influence of phylogeny, social style, and sociodemographic factors on macaque social network structure

Krishna Balasubramaniam (1) , Brianne Beisner (1) , Carol Berman (2) , Arianna de Marco (3) , Julie Duboscq (4) , Sabina Koirala , Bonaventura Majolo (5) , Andrew Macintosh (4) , Richard Mcfarland (6) , Sandra Molesti (7) , Hideshi Ogawa (8) , Odile Petit (9, 10) , Gabriele Schino (11) , Sebastian Sosa (12) , Cédric Sueur (13) , Bernard Thierry (10) , Frans de Waal (14) , Brenda Mccowan (1)

1 UC Davis - University of California [Davis]
2 SUNY Buffalo - University at Buffalo [SUNY]
3 Department of Animal Biology and Genetics
4 Kyoto University
5 University of Lincoln [UK]
6 University of Wisconsin-Madison
7 CLLE-LTC - Cognition, Langues, Langage, Ergonomie
8 School of international liberal studies
9 Ethologie Cognitive et Sociale
10 IPHC - Institut Pluridisciplinaire Hubert Curien
11 Istituto di Scienze e Tecnologie della Cognizione
12 SYSU - Sun Yat-sen University [Guangzhou]
13 DEPE-IPHC - Département Ecologie, Physiologie et Ethologie
14 Emory University [Atlanta, GA]

Among nonhuman primates, the evolutionary underpinnings of variation in social structure remain debated, with both ancestral relationships and adaptation to current conditions hypothesized to play determining roles. Here we assess whether interspecific variation in higher‐order aspects of female macaque (genus: Macaca ) dominance and grooming social structure show phylogenetic signals, that is, greater similarity among more closely‐related species. We use a social network approach to describe higher‐order characteristics of social structure, based on both direct interactions and secondary pathways that connect group members. We also ask whether network traits covary with each other, with species‐typical social style grades, and/or with sociodemographic characteristics, specifically group size, sex‐ratio, and current living condition (captive vs. free‐living). We assembled 34–38 datasets of female‐female dyadic aggression and allogrooming among captive and free‐living macaques representing 10 species. We calculated dominance (transitivity, certainty), and grooming (centrality coefficient, Newman's modularity, clustering coefficient) network traits as aspects of social structure. Computations of K statistics and randomization tests on multiple phylogenies revealed moderate‐strong phylogenetic signals in dominance traits, but moderate‐weak signals in grooming traits. GLMMs showed that grooming traits did not covary with dominance traits and/or social style grade. Rather, modularity and clustering coefficient, but not centrality coefficient, were strongly predicted by group size and current living condition. Specifically, larger groups showed more modular networks with sparsely‐connected clusters than smaller groups. Further, this effect was independent of variation in living condition, and/or sampling effort. In summary, our results reveal that female dominance networks were more phylogenetically conserved across macaque species than grooming networks, which were more labile to sociodemographic factors. Such findings narrow down the processes that influence interspecific variation in two core aspects of macaque social structure. Future directions should include using phylogeographic approaches, and addressing challenges in examining the effects of socioecological factors on primate social structure.

Mots clés: Social networks; Phylogenetic signals; Social style; Group size; Macaques; Social networks

Domaines: Zoologie des vertébrés; Sciences de l'environnement

Krishna Balasubramaniam, Brianne Beisner, Carol Berman, Arianna de Marco, Julie Duboscq, et al.. The influence of phylogeny, social style, and sociodemographic factors on macaque social network structure. American Journal of Primatology, 2018, Special Section on Chimpanzee Health and Conservation in the Anthropocene, 80 (1), pp.e22727. ⟨10.1002/ajp.22727⟩. ⟨hal-01715327⟩