Meeting Abstract

P1.19  Saturday, Jan. 4 15:30  Behavioral and Neural Correlates of Invasive Ability in Lizards DAVIS, L.M.*; JOHNSON, M.A.; Trinity University ldavis1@trinity.edu

Efforts aimed at detecting and managing potentially invasive populations typically focus on understanding the ecological, genetic, and life history characteristics of invasive organisms. However, an understanding of the behaviors underlying invasion success is lacking. This study explored invasive behavioral mechanisms by comparing the “boldness” behaviors of three lizard species that vary in invasive ability. This syndrome correlates aggressive behavior with high activity levels and behavioral flexibility, all of which play an important role in the invasion process. The species studied include the non-invasive green anole (Anolis carolinensis), the invasive brown anole (A. sagrei) from both native and invasive ranges, and the less invasive bark anole (A. distichus) from its native range. We measured boldness by conducting a series of four behavioral tests on 12 males per species, including tests measuring aggression towards prey, aggression towards a conspecific, overall level of activity, and behavioral flexibility. Preliminary analyses suggest that the invasive brown anole is “bolder” than the native green anole in three of the four behavioral tests, and that the bark anole is “bolder” than the brown anole in two of the four tests. In addition, brain to body mass ratios, generally associated with behavioral flexibility, are significantly higher in the native green anole than the invasive brown anole. The native brown anole and the trunk anole did not differ in the brain to body mass ratio. Our future work will examine neuron size and density in three brain regions involved in aggression and exploratory behavior: the amygdala, the hippocampus, and the hypothalamus. By understanding the behavioral and neural differences between invasive and non-invasive lizards, we may better prevent and predict future vertebrate invasions.