Ask Dr. Universe

How does a chameleon change colors? Asked by Jasmine B. 12, Nepean, Canada and Marie F., 11, Ghana.

Dear Jasmine and Marie,

There’s something about a chameleon’s darting eyes, long tongue, curled tail and ability to climb that makes it a fascinating animal to watch. Especially when it’s changing colors.

And the latest research on your question suggests that how a chameleon changes has more to do with light than scientists once thought.

That’s what I learned from my friend Paul Verrell, a biologist at Washington State University who studies animal behavior and works with reptiles. He said not a...