Honest olfactory ornamentation in a female‐dominant primate

Abstract

Sexual selection theory predicts that potential mates or competitors signal their quality to conspecifics. Whereas evidence of honest visual or vocal signals in males abounds, evidence of honest signalling via scent or by females is scarce. We previously showed that scent marks in male lemurs seasonally encode information about individual heterozygosity – a reliable predictor of immunocompetence and survivorship. As female lemurs dominate males, compete over resources, and produce sexually differentiated scent marks that likely evolved via direct selection, here we tested whether females also advertise genetic quality via olfactory cues. During the breeding season specifically, individual heterozygosity correlated negatively with the diversity of fatty acids (FAs) expressed in labial secretions and positively with the diversity of heavy FA esters. As odour–gene relationships predictive of health and survivorship emerged during a period critical to mate choice and female competition, we posit that genital scent marks function as honest olfactory ornaments in females.

Smelling wrong: hormonal contraception in lemurs alters critical female odour cues

“…We conducted our study during the species's breeding season, which in the Northern Hemisphere spans from late October to early February [23]; however, for comparative purposes, some of our analyses also include chemical data derived from previous studies of the same animals conducted in both the breeding and non-breeding seasons [22,[26][27][28]. All of the subjects were socially housed, as described elsewhere [25].…”

Baby on board: olfactory cues indicate pregnancy and fetal sex in a non-human primate

“…Among females, which use scent to demarcate birthing sites [12] and for competitive overmarking [7], variations in odorant profiles (whether in compound type, number or relative concentration, see e.g. diversity indexes in Charpentier et al [13]) correspond to natural [14,15] and experimentally induced [16] variations in reproductive hormones. Through behavioural bioassays, genetic profiling and chemical analyses, lemur chemosignals have been shown to convey information about sex, breeding condition and individual identity, as well as genetic quality and relatedness (reviewed in [7,16]).…”

Socioecological and phylogenetic patterns in the chemical signals of strepsirrhine primates

“…Lemur catta arguably possesses one of the most complex olfactory repertoires of any of the strepsirrhines (Schilling, 1974), which, like that of sifakas (Lewis, 2006), includes the use of composite, multimodal signals (Drea & Scordato, 2008). The chemistry of their volatile urinary (delBarco-Trillo et al, 2011) and glandular signals (Boulet et al, 2009(Boulet et al, , 2010Charpentier et al, 2008;Crawford et al, 2011;Hayes et al, 2004;Palagi & Dapporto, 2006;Scordato et al, 2007) has been well characterized. Notably, whereas the genital secretions of males and females in any species of Eulemur examined to date contain fewer than 30 compounds (delBarco-Trillo et al, 2012), hundreds of compounds have been detected in the genital secretions of male and female L. catta (Boulet et al, 2009;Scordato et al, 2007).…”

“…, identity (Palagi & Dapporto, 2006;Penn et al, 2007;Scordato et al, 2007;Smith, Tomlinson, Mlotkiewicz, & Abbott, 2001) and 'quality' (as estimated by genetic diversity: Boulet, Crawford, Charpentier, & Drea, 2010;Charpentier, Boulet, & Drea, 2008; as estimated by major histocompatibility complex genotype: Setchell et al, 2011), as well as the genetic relatedness between individuals (Boulet, Charpentier, & Drea, 2009;Charpentier et al, 2008;Morelli et al, 2013).…”