VINCENT, SE*; HERREL , A; IRSCHICK, DJ; Tulane University; University of Antwerp; Tulane University: Kinematic comparisons of aquatic and terrestrial predation in a pitviper, Agkistrodon piscivorus

Aquatic foraging in snakes has evolved independently in several different clades of snakes. Thus, aquatic foraging in snakes presents an exceptional opportunity to study convergent evolution in vertebrate feeding systems. The predatory strikes of piscivorus snakes function in an environment eighty times as viscous and nine hundred times denser than air. Thus, snakes should strike laterally in order to minimize both the drag and bow waves generated by the head. However, recent studies have shown that at least a few species of smaller piscivorus natricines ( Thamnophis, Nerodia ) are forward strikers. The pitviper Agkistrodon piscivorus is the only member of Viperidae known to forage aquatically. Young (1991) hypothesized that the bulky triangular shaped head of A. piscivorus would dictate this species to be a lateral striker during aquatic feeding. Our study, however, shows that this species is in fact a forward striking aquatic forager. We used high-speed cameras to film both the aquatic and terrestrial predatory strikes of A. piscivorus. We discuss here a three-dimensional kinematic comparison of aquatic and terrestrial predatory strikes of A. piscivorus. This study was financially supported by a NSF grant (IBN 998300) to D.J. Irschick.