The color change from a bright, vibrant green to a dull, muddy brown is one of the most characteristic qualities of the green anole (Anolis carolinensis) (I am aware that some dewlap enthusiasts may take issue with this statement). Given the dramatic differences between the colors, Daisy Horr, a Junior in the Johnson Lab at Trinity University in San Antonio, TX, wondered how social behavior and body temperature may influence body color, and whether these relationships differ between males and females.
First, Daisy observed green anole social behavior in Palmetto State Park, TX, and found that males exhibited green body color more frequently than females, and males that performed more pushup and head bob displays also changed colors more frequently (between green and brown). She also found that females were more often green during social interactions.
Because green anoles are ectothermic, more commonly known as cold-blooded, ambient temperature plays an important role in nearly every aspect of their lives. Therefore, there might be a relationship between body color and thermoregulation. Daisy spent a lot of time searching the Trinity University campus for green anoles, and measured body temperatures, the temperatures of the perch on which she found them, and the distance to the nearest alternative perch (a measure of exposure). While she did not find any association between body color and temperature, she did show that males used warmer substrates than females, and that males were typically more exposed (greater distance to the nearest perch). Additionally, she found that males are generally greener than females throughout the day.
Daisy plans to pursue graduate school after she finishes at Trinity University, and we all hope she continues to contribute to anole research! Graduate advisors, you don’t want to miss out on a fabulous researcher!
(This post’s author’s diploma from Trinity University does not affect his assertion that Trinity graduates are among the best minds in biological research.)