Meeting Abstract
There is constant competition between animals over necessary resources, such as food, water, and reproductive partners, and aggression is a strategy employed to defend resources. Territorial aggression over access to mates is well-studied, however much less is understood regarding aggression aimed at securing food supplies. During a period of food insecurity, the value of food increases which may increase the motivation for defense. We tested the hypothesis that food insecurity increases agonistic behavior, a term encompassing both direct aggression and associated ritualized display behaviors, in male brown anoles (Anolis sagrei). We developed three methods for inducing food insecurity and then measured resulting agonistic behaviors. First, to simulate a complete loss of food availability, lizards were fasted for durations of 24, 48, or 72 hours and then tested against fed control lizards in a video-recorded dyadic encounter, where agonistic behaviors were scored. Second, to simulate an unpredictable food source, the amount and timing of food presentation was randomized and those individuals were again tested in a dyadic encounter against control lizards that had daily access to food with both groups equal in the total amount of calories made available to them. Third, to simulate a decrease in food availability, treatment lizards were fed crickets of a smaller size (i.e., fewer calories) and were tested against control lizards fed the normal caloric amount. Results reveal that current energetic state impacts the propensity towards agonistic behavior, with an upper limit imposed in cases of severe energy deprivation. Current research is focused on the potential role of a neural regulator of food intake, neuropeptide Y, in influencing agonistic behaviors.
