Is Brightest Best? Testing the Hamilton-Zuk Hypothesis in Mandrills

Abstract

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Odour signals major histocompatibility complex genotype in an Old World monkey

“…[44] for lemurs). This contrasts with the degree of facial red colour in male mandrills, which is associated with possession of some of the same MHC supertypes [45], and raises the possibility that visual traits signal the possession of particular genotypes, while odour signals other aspects of the genotype (diversity and similarity). A similar scenario under which visual and olfactory communication act in a complementary fashion has been proposed for humans, in which facial attractiveness appears to signal MHC similarity, while odour signals MHC dissimilarity [46].…”

Color in competition contexts in non-human animals

“…However, correlational studies provide weak tests of the relationship between ornaments and condition (Cotton, Fowler, & Pomiankowski, 2004), and improved measures of immune system quality are needed for a robust test of the hypothesis that colour signals health in this species. Red is also unrelated to either overall genetic diversity or to MHC diversity (Setchell et al, 2009). However, red is related to the possession of specific MHC genotypes, providing some support for the hypothesis that red colour advertises 'good genes' in mandrills, if these genotypes are beneficial in terms of health.…”

“…For example, colour in mandrills is part of a suite of visual, olfactory and acoustic traits (Darwin, 1871;Osman Hill, 1970). While male mandrill colour and odour both signal age and rank, they also reflect different aspects of the male: red signals testosterone and some MHC genotypes, while odour encodes genetic diversity and genetic similarity (Setchell et al, 2011(Setchell et al, , 2009Setchell, Vaglio, et al, 2010). Similarly, red colour and barks in male rhesus macaques have the potential to convey different information to the perceiver (Higham et al, 2013).…”

“…Red is not related to parasite load or to haematological parameters in individual males (Setchell et al, 2009). There is, thus, little support for the Hamilton-Zuk hypothesis of parasite-mediated sexual selection (Hamilton & Zuk, 1982) as an explanation for male colour in mandrills.…”

“…The mandrill is the only primate species in which the relationships among skin colour, parasites, body condition, immune parameters, genetic quality, androgens and glucocorticoids have yet been examined in detail (Setchell, Charpentier, Abbott, Wickings, & Knapp, 2009;Setchell, Smith, Wickings, & Knapp, 2010). Red is not related to parasite load or to haematological parameters in individual males (Setchell et al, 2009).…”