Abstract # 243:

Scheduled for Saturday, June 20, 2015 01:00 PM-01:30 PM: (Cascade F) Oral Presentation


L. A. Isbell
Department of Anthropology, University of California , Davis, CA 95616, USA
     Primates are distinguished from other mammals in large part by their highly developed visual sense. Several hypotheses have been developed to explain this evolutionary innovation, including the recent Snake Detection Theory (SDT) (Isbell 2006, 2009). The SDT proposes that the expansion of the primate visual system occurred as a result of selection favoring avoidance of predation by snakes via early visual detection. Thus, according to the SDT, the primate lineage was established through interactions with constricting snakes, while the later appearance of venomous snakes intensified selection on the visual systems of anthropoid primates to different degrees depending on the extent of their evolutionary co-existence on the landmasses of Africa/Asia and Central/South America. Here I describe the SDT in detail, highlighting indirect evidence employed in its initial development. The SDT provides a contextual and adaptationist platform for the talks that follow in this symposium, all of which emphasize the close relationship between primates and snakes.