Strike-Induced Chemosensory Searching in Reptiles: A Review

Abstract: Chemosensory searching in squamates with specialized tongue–vomeronasal systems is well-documented. By tongue-flicking, these reptiles gather important chemical cues from their environment to guide their feeding behavior. Strike-induced chemosensory searching (SICS) is a specific expression of chemosensory reception that is central to the predatory strategy used by venomous reptiles that strike, release, and relocate their prey. This complex behavioral process consists of multiple sequential steps and has been mainly studied in viperids, particularly rattlesnakes. Although this phenomenon has been extensively researched, there is no comprehensive review of the SICS literature. Here, we provide such a review, centered on the idea that SICS is a result of suppression, and then enhancement, of chemosensory searching that serves as a key element of the ambush hunting strategy that most viperid snakes use to consume large and well-defended prey. SICS is also present in other venomous and nonvenomous taxa, and we include a taxonomic categorization of SICS studies in our review. We summarize the key findings discovered during decades of research into this remarkable feeding behavior and highlight areas where our knowledge remains incomplete in an effort to foster further research that will increase our understanding of reptilian feeding ecology.