Learn a Little: Chuckwallas

If you’ve seen the chuckwallas in the Discover Exhibit, you may have noticed that they have a lot of wrinkles and excess skin on their sides, as well as a wide and flat body shape. Did you know there’s a purpose for this extra skin and body composition, and it involves rocks?

In the wild, if chuckwallas are threatened or startled, they will take shelter in tight spaces like rock crevices found in outcrops and rocky hillsides. It’s easier to fit in these tight spaces thanks to their wide, flat body shape. They then inflate their lungs by gulping air and wedging themselves in the crevice. When they inflate their lungs, the excess folds of loose skin will stretch, similar to blowing up a balloon. This allows them to fit tightly, ultimately becoming stuck between the rocks. It is now much more difficult for a predator to grab them or pull them out.

In addition to providing a safe refuge for chuckwallas, rocks also provide warmth.
As ectotherms, these lizards require an external source for body heat. The rocks are warmed by the sun and provide a basking area for chuckwallas and other reptiles to stay warm.