The Herpetological Journal

pp. 131-138
Authors: Briggs, Venetia S.

Abstract: Under the good genes model of sexual selection, females prefer males with attributes that signify high genetic quality to improve offspring fitness. This study tested the hypothesis that female mating preferences result in enhanced offspring performance, owing to genetic variation among sires in two species of red-eyed treefrogs (Agalychnis callidryas and A. moreletii). The study provides evidence for paternal size effects on offspring traits, most notably on hatchling size, larval duration and size at metamorphosis. Large males of both species produced larger hatchlings relative to half-sibs. Larger hatchlings may have immediate growth and survival advantages that propel them through the larval period and suggests the potential for increased post-metamorphic fitness benefits. Large males of A. callidryas sired larger froglets and there were positive correlations between sire size and froglet traits for both species. Tadpoles of both species that remained in a longer larval period emerged from metamorphosis at a greater size. The two species share similar life history traits, but considerable inter-specific differences of paternal effects between A. callidryas and A. moreletii may help to explain the variation in breeding behaviour and tadpole biology within these two species. In this system, females may exercise directional selection for offspring at a larger metamorphic body size that will increase her fitness through enhanced survival and reproductive success.

Keywords: GOOD GENES, A. MORELETII, FEMALE CHOICE, AGALYCHNIS CALLIDRYAS, SEXUAL SELECTION, TADPOLE TRAITS