Male-male competition is one of the most widespread phenomena in lizards. Males compete for access to critical food resources, territory space, and female lizards, making a male’s ability to win competitions against other males critical to survive and reproduce. However, how the behavior of a male can vary depending on what social environment he grew up in, the abundance of certain predators or competitors, or the density of other male and female lizards. Therefore, determining what environmental factors influence the behavior of male lizards as they attempt to procure resources necessary to survival and reproduction is a critical question in biology today.
From Virginia Tech, (now a Ph.D. student with Shawn Kuchta at Ohio University) Emily Watts and her collaborators sought to understand what environmental factors influence the behavior of male brown anoles (Anolis sagrei). They used males reared in a common garden from four different populations in the Bahamas to try and determine if genetic or environmental factors influence the aggression differences among males of different populations. Using male-male competition experiments and mirror experiments (where a single male perceives himself as a rival), they tested the hypothesis that males reared in a common garden will not differ in aggressive behavior. They found that aggression varied significantly among populations when using mirror tests, but they found support for their original hypothesis when using male-male competition experiments. This work highlights that aggressive behavior of males is shaped by a multitude of pressures from the environment, to genetics, and ultimately how and where a lizard develops to adulthood. More is to come as they continue to increase the number of their experimental trials with more Anoles!