REILLY, S.M.; MCBRAYER, L.D.*; Ohio University; Stephen F. Austin State University: Prey capture and prey processing behavior and the evolution of lingual and sensory characteristics: divergences and convergences in lizard feeding biology

A central element of the sit-and-wait vs. wide foraging paradigm involves the tradeoff between prey capture function and chemosensory acuity. In general ambush feeders are thought to use the tongue primarily to capture prey located visually, while wide foragers are thought to have traded tongue based prey capture for tongue flicking which is critical to locating widely dispersed prey using chemoreception. The switch to chemosensory tongue function among scleroglossan lizards is certainly linked to their wide foraging strategy, and in fact, this transition has enabled wide foragers to dominate lizard communities worldwide. Here, we examine the trade off between feeding behaviors (prey capture and subsequent processing) and chemosensory function in lizards with data available to date. First, we review kinematic patterns of �prey capture� behaviors. This analysis illustrates three basic prey capture modes (tongue prehension, translational tongue prehension, jaw prehension). Next, we review patterns of post-capture prey processing behavior that reveal three evolutionary shifts in lizard �chewing� behavior. Finally, we compare changes in lizard feeding behavior with quantified characteristics of the vomeronasal system, tongue morphology, prey discrimination ability, and foraging behavior from the literature to examine how changes in feeding function correlate with changes in chemosensory function. The behavioral and morphological data show that the Iguania have shifted to a novel tongue projection strategy and that the advent of chemosensory dedicated tongue function is not a scleroglossan trait but has independently evolved with wide foraging twice, once within the Lacertoidea, and once within the Anguimorpha.