You walk into our Visitor Center and see one of the many reptiles that we care for here, an anole! She is a bright green with a little spot of blue right around her eye. At first, she’s very hard to spot because she was hiding in the green leaves of her enclosure. You go for a walk and come back. Wait, now there’s another one in there with her – a brown one!
Nope, we promise, there’s only one anole lizard in our Green Anole enclosure! Green Anoles, otherwise referred to as the American Chameleon (to which they are not related), have the unique capability to change their color by controlling various pigments in specialized cells called Chromatophores. Light reflects off of these pigments and hit our eyes, causing us to see varying shades of color. Green Anoles, like our Green Girl, can change from a bright green to a deep brown depending on a wide variety of factors. In fact, lots of research and study has gone in to why Anoles will change color and the results are inconclusive.
The first reason that they might change color is due to social interactions. Males may change from green to brown when in an aggressive encounter with other males. They are very territorial animals, and therefore can change color when stressed and angered. By the end of the territorial dispute, the dominant male will come away green and the loser will still be brown. Often their coloration is a means to attract attention. In the case of mating, females will often use their coloration to signal that they are ready to mate. Males have a flap of skin under their neck called a Dewlap that turns to a vivid pinkish color when trying to attract mates.
The next reason that they may change colors is due to individual stress. There are many variables that affect the happiness of anoles such as humidity, temperature (Anoles are ectotherms – they can’t thermoregulate), predation attempts, and light levels. For instance, if the lizard is cold, it may turn from the vivid green to the dark brown in hopes of absorbing more heat.
Finally, the last reason that they would change colors is for camouflage. Small lizards are easily predated upon and being able to change color in order to hide can help the little critters survive! This however, is not the only reason that they change color, and many times their color does not match their environment, suggesting that this is not the most important reason for their color change.
In our Green Anole, Green Girl, she will often change from brown back to green once she has caught her cricket meal, from a dull to vivid green after shedding, is often a dull brown during the winter months, and from green to brown as soon as we use a water spray bottle to douse her leaves and add some moisture to the enclosure. Since there is no male in the enclosure with her, this suggests to us that her mood is one of the most important factors in her color changes!
Stop by our Visitor Center Monday-Friday, 10am-4pm, or Saturday and Sunday, 10am-4pm to hang out with our animals! Interested in learning more about reptiles and amphibians (herps) of the Bucks County Area? Click on the links below and join Bucks County Audubon Society for our annual PA Amphibian and Reptile Survey (PARS) on August 27th at 2pm!