Zoological Studies

Agonistic Behavior of the Mediterranean Gecko Hemidactylus turcicus

Venetia S. Briggs (2012) Agonistic behavior may influence the dispersal of species and spatial distribution of individuals within a population.  The Mediterranean gecko Hemidactylus turcicus was used to test 2 hypotheses: 1) adult behavior differs in responses to conspecifics and resource limitations; and 2) juvenile behavior is affected by visual, chemical, and tactile adult male cues.  I quantified behavioral responses of males to different levels of food quality, availability of retreat sites, and the presence of a resident male.  Aggression was significantly more prevalent in the presence of a conspecific male regardless of resource availability.  To test the 2nd hypothesis, I observed juvenile responses to chemosensory cues of either a confined or non-confined adult male.  Both visual and chemosensory cues combined, rather than chemical cues alone influenced juvenile responses.  Juveniles also exhibited sensory behavior (tongue-flicking) upon entering a novel environment, indicating that chemical mediation may be sufficient to impact behavior.  Results of these contests illustrate the importance of chemical communication in providing information which influences behavioral responses and suggests a role for self and mutual assessments during intraspecific encounters.  The outcome of competitive encounters may heavily rely on information collected via chemical cues and may ultimately regulate aggression by informing individuals about whether or not to fight and thus adhere to the confines of social dominance within the species.