Androgen levels and female social dominance in Lemur catta

Morphological and behavioural traits which improve agonistic power are subj ect to intrasexual selection and, at the proximate level, are influenced by circulating androgens. Because intrasexual selection in mammals is more in tense among males, they typically dominate females. Female social dominance is therefore unexpected and, indeed, I arc. Ring-tailed lemurs (Lemur catt a) are sexually monomorphic primates ill which all adult fc males dominate all males. The goal of our study was to test the prediction that female dom inance in this species is associated with high androgen levels. Using two c aptive groups, we collected data on agonistic behaviour and non-invasively assessed their androgen concentrations in faeces and saliva Ly enzyme immun oassay. We found that adult female L. catta do not have higher androgen lev els than males. However, during the mating season there was a twofold incre ase in both the androgen levels and conflict rates among females. This seas onal increase in their androgen levels was probably not due to a general in crease ill ovarian hormone production because those females showing the str ongest signs of follicular development tended to have low androgen concentr ations. At the individual level neither the individual aggression rates nor the proportion of same-sexed individuals dominated were correlated with th eir. androgen levels. We conclude that female dominance in ring-tailed lemu rs is neither based on physical superiority nor. on high androgen levels an d that it is equally important to study male subordination and prenatal bra in priming effects for a complete understanding of this phenomenon.