Lizard sleeping.

I’d been wondering about this little lizard for a while. Why is he white? I found him at night at La Selva Biological Station in Costa Rica and tried to ID him several times. I was pretty sure he was a species of anole lizard but got nowhere until I found the following Wikipedia entry on anole lizards: “Their colors during the night when sleeping often differ distinctly from their colors during the day when awake. Among these are some species that otherwise do not drastically change their colors, including certain anoles that generally are brown during the day changing to greenish or whitish when sleeping at night.”

Apparently, what I'd found was one of the local anole species who had turned this grey and white color while he slept. Corrections welcome on this!

During the day, most anoles can change color. The Carolina anole (which is the only native US anole species) can change from green to brown in a matter of a few minutes. The color change is triggered by a release of hormones and occurs for a variety of reasons including stress, temperature, display and aggression.

What I didn't know is that they can turn their color off at night which is what this little guy had done and how I spotted him.