Summary:
- Chameleons are a distinctive and highly specialized type of lizard.
- They are distinguished partly by their parrot-like feet, their separately mobile and stereoscopic eyes, their very long, highly modified, and rapidly extrudable tongues, crests or horns on their heads.
- There are more than 8,200 living species of reptiles, and they are placed in four orders: Crocodilia, which includes crocodiles and alligators; Sphenodontia, or tuataras; Squamata, which including lizards and snakes; and Testudines.