As a senior in college I wanted to study courtship behaviors, and the brown anole (Anolis sagrei) piqued my interest. In going through the literature, I noticed that some studies reported finding evidence for the presence of female choice in brown anoles and others reported that female choice didn’t occur in the species. So I decided to see if females exhibited a preference for males based on two different characteristics: male physiology and male territory quality, each of which would provide females with different benefits. I expected that females would choose males based on territory quality, because females usually mate with the males whose territories overlap theirs in the wild.
I tested for female preference in two different choice experiments using anoles that I ordered and had sent to my college, Colby College, in Maine. I was given access to a small storage closet (which I cleaned out) in the basement of Colby’s biology building in which I kept my crickets and anoles. To test for differences between males with different physiological traits, I tested male endurance by placing them on a treadmill and running them until they couldn’t run any longer. This was perhaps one of the most stressful parts of the experiment for me, since the lizards really didn’t like being put on the treadmill, so during this part of the experiment I got to chase many lizards around the room.
A brown anole running on a lizard treadmill
I then paired similarly-sized males with very different running times to see if females spent more time with one male over the other. For the preference tests, the males were tethered to posts in a mate choice box originally constructed for zebrafinches, and the females were able to run freely through the box.
In the territory tests, rather than pairing males with different endurance scores, I randomly placed males on the side of the box with many plants and twigs, or on the side without. In both tests, I recorded the amount of time females spent on either side as well as the behaviors of the males and females (I watched many hours of video to score behaviors).
Mate choice arena for the territory quality experiment
My results were somewhat surprising; I found that in both experiments the more active male was the most preferred one. This was contrary to my prediction, especially since our measure of activity included all male behaviors, not just courtship behaviors. This is not surprising in the broader scheme of mate choice, since active mates are often preferred, and it’s interesting to see how anoles fit into the bigger picture of mate choice and sexual selection in general. This study is now published, so check it out if you’re interested in the details! Please feel free to contact me if you have any questions or would like a copy of the pdf.