title: Adaptive response to sociality and ecology drives the diversification of facial colour patterns in catarrhines.
abstract: The faces of Old World monkeys and apes (Catarrhini) exhibit every possible hue in the spectrum of mammal colours. Animal colouration experiences selection for communication, physiology and ecology; however, the relative importance of these factors in producing facial diversity in catarrhines is not known. Here we adopt a comparative approach to test whether facial traits have evolved in tandem with social, geographic and ecological pressures across four catarrhine radiations. Our analyses reveal the underlying correlates of two major axes in the evolution of facial diversity. Facial colour patterns are linked to social factors, such that gregarious and highly sympatric species have evolved more colours in their faces. Facial pigmentation tends to be dominated by ecological factors, and species living in tropical, densely forested and humid habitats in Africa have evolved darker faces. Thus, both sociality and ecology have played a role in producing the highest diversity of faces within mammals.
authors.affiliation: Department of Biology and Burke Museum of Natural History and Culture, University of Washington, Seattle, Washington 98195, USA.
authors.forename: Sharlene E
authors.initials: SE
authors.lastname: Santana
authors.forename: Jessica Lynch
authors.initials: JL
authors.lastname: Alfaro
authors.forename: Andrew
authors.initials: A
authors.lastname: Noonan
authors.forename: Michael E
authors.initials: ME
authors.lastname: Alfaro
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D051079:Catarrhini / Q000502:physiology*; D017753:Ecosystem; D005145:Face; D010860:Pigments, Biological / Q000502:physiology*; D012919:Social Behavior; D013045:Species Specificity
chemical_list: D010860:Pigments, Biological