CONICET | Buscador de Institutos y Recursos Humanos

Fossorial habits occur in many animal lineages and usually involve both morphological and physiological adaptations thatmay evolve independently.Burrowing behavior in some species of the anuran subfamily Leptodactylinae involves the specialized use ofthe hind limbs and/or head. The aim of this study was to identify the morphometric characters associated with burrowing behavior inspecies of this subfamily. We then hypothesized that, as this habit is usually associated with males, we would ﬁnd sexual dimorphism inhead and hind-limb morphology in the burrowing species but not in the nonburrowing species. We compared 500 specimens from 24species using phylogenetic statistical analyses and phylogenetic mapping of sexually dimorphic characters. The results demonstrated thefollowing: 1) There was no correlation between the measurements of the limbs, head, or tarsal tubercle and burrowing behavior in theanalyzed species; 2) there was no sexual dimorphism related to burrowing behavior reﬂected in measurements of the head or hind limbs;and 3) sexual dimorphism in the morphometric characters always was derived. Modiﬁcations of the ridged snout and increasedossiﬁcation in the nasal region of the males of the fossorial species appear to be sufﬁcient adaptations for burrowing.