Snakes, tongue-flicking patterns

Traversing a maze in which no proximate odor cues are present, but in which snakes have previously received rewards was here defined as a foraging task. Such a task permits one to analyze tongue-flick patterns before and after prey consumption. 

Patterns of Tongue-Flicking by Garter Snakes (Thamnophis sirtalis) during Presentation of Chemicals under Varying Conditions... 

It is well known that the chemical senses play a critical role in the behavior of snakes (Halpern, 1987, 1992 Mason 1992 and Schwenk 1995). Tongue-flicking, a chemosensory behavior pattern unique to snakes and lizards (Gove 1979 Schwenk 1993), serves as the primary vehicle for transfer of chemical substances to the vomeronasal organ (Burghardt and Pruitt 1975 Graves and Halpern 1989 Halpern and Kubie 1980 Kahmann 1932 Wilde 1938). Snakes have well-developed vomeronasal systems and flick their tongues in response to odorants perceived in their environment. 

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