Sex determination in adults of two otariid species (Neophoca cinerea and Arctophoca australis forsteri) based on osteology of the pelvis

摘要

Pinniped comparative anatomy has focused mainly on establishing taxonomic differences (Howell 1929, King 1966, Brunner 2004), and functional morphology in otariids (English 1976, 1977). The latter studies focused on forelimbs as the Otariidae is the only marine mammal group that uses highly modi?ed fore?ippers as the primary mode of propulsion (Feldkamp 1987) (while the polar bear also uses its forelimbs for swimming [Pabst et al. 1999, Fish 2004], its limbs are not modi?ed into ?ippers). Very few anatomical studies on sexual dimorphism in pinnipeds exist, yet sexual dimorphism has been linked with polygyny in this group (Bartholomew 1970, Boness 1991).