This taxonomic, phylogenetic and functional studies of fossil walruses (Odobenidae sensu Demere) will focus on exceptionally well preserved and systematically informative skeletal material from the Emlong Collection (USNM, Smithsonian Institution). Specific objectives of this qtudy are: (1) to document odobenid diversity form the early Miocene through the Pliocene (17-3 million years ago), (2) to evaluate the systematic relationships of these Neogene odobenids that are especially critical to walrus phylogeny, and (3) to use this phylogenetic framework to investigate adaptation of feeding strategies and locomotor patterns among odobenids and related pinnepeds (seals and sea lions).