Central and endocrine aspects of tongue-flicking and exploratory behavior in Anolis carolinensis

Tongue-flicking in reptiles is frequently seen to increase in novel habitats and is presumed to involve the acquisition of chemical information. Like most behavioral patterns, however, tongue-flicking has both multiple causes and multiple functions, only some of which involve chemosensation. This paper describes units of exploratory behavior, including use of the tongue, in a microsmatic lizard, the green anole, Anolis carolinensis. This species employs its tongue in a manner suggestive of chemosensory exploration, but it possesses modest peripheral chemosensory organs and reduced central representation of chemosensory target cell groups. Further, specific elements of exploratory behavior are affected differently by treatments that involve altering levels of stress-sensitive hormones, androgen, and central catecholamines. Such differential responses suggest that exploratory behavior is an ensemble of individual units, some of which are selectively sensitive to specific physiological elements of the stress response and of elevated arousal.