A guest blog post by Aquarium Herpetologist MacKenzie Mathis
Have you ever wondered why a specific animal is classified as a lizard?
There are several reasons as to why a lizard is, in fact, a lizard. To begin, lizards are reptiles. This excludes animals like salamanders which are actually amphibians.
Lizards have dry, scaly skin that typically sheds in multiple pieces (unlike most snakes), although some do shed in a single or very few pieces. Salamanders have moist skins. Crocodilians don’t shed their scales.
In addition to these characteristics, several other factors are involved in classifying a reptile as a lizard, snake, turtle/tortoise, or crocodilian.
The majority of lizard species have 4 legs and a tail. Their legs are placed out to the sides of their body and have five toes on every foot. Lizards tend to have a long, relatively slender body plan.
But just when you thought identifying lizards would be easy, there are some species that have adapted to become legless (ex. glass lizards).
Some lizards can change color (ex. chameleons, anoles, etc.). These color changes are a type of communication that allows some species of lizards to convey their mood (ex. attracting a mate, scared and wanting to escape danger, happy and doing well, sick/injured and not feeling well, etc.). These different emotions dictate the color changes that can be seen in these species. They are brighter in color when they are doing well or trying to attract a mate and darker in color if they are in danger or sick/injured. Contrary to belief, color changes are not used for camouflage (although the color changes do sometimes help them to better blend in with their surroundings).
Lizard species that have the ability to change color, don’t have the ability to change to any color. These species have the ability to brighten or darken the colors that are already present on their bodies or change to black by bringing melanin (dark pigmentation) to the surface of their skin.
Some lizard species have the ability to drop and regrow their tails ( some geckos, skinks, etc.). This is a strategy to distract a predator and is called autotomy.
Some lizards also have prehensile tails that they can use to wrap around branches. Their tails act like an extra foot. Others have strong, powerful tails that they can use in defense.