You're full of hot air! An insult, right? Not for a lizard adapted to living in rocky habitats with abundant crevices. Crevices are ideal for escaping predators. Just duck into one and you're safe. Or rather, you would be if a crevice was of an ideal size and shape. But if it was a little too large and a bit too shallow, many predators could just drag you out. Some of the spiny lizards have a solution—not a perfect one, but one that works often enough. Just bloat yourself with air, wedging your body firmly against the crevice walls. You might get torn up a bit, but that sure beats being dragged into the open where powerful jaws would quickly put an end to life.
This is efficient enough that, between the difficulty of getting a good
hold and the bloating strategy, a spiny lizard can as often as not resist even a
human's pull. Unfortunately for the lizard, humans, unlike most other predators,
have recourse to tools, and hot air does little good in this case. 
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.