Window on Nature
By Lowell & Kaye Christie, F47246
September 2005
Many people don’t like lizards any more than they do snakes, but we find these creatures interesting and often delightful. There are more than 100 species of lizards in the United States that sport a variety of shapes, patterns, and colors.
Lizards can be found in every state except Alaska, but the greater numbers occur where temperatures are warm. We’ve never seen as many lizard species as we did during our stay in the south Arizona desert. At our home in the Sierra foothills of central California, we almost never spot them. That’s partly because these natives aren’t such flashy dressers, so they often escape our notice.
Lizards live in a wide variety of habitats, from deserts and forests to the fringes of marshes and streams. They make their homes in subterranean burrows and rocky outcrops. And, from what we’ve read, they even hang out in the tops of trees. Keep your eyes open, because wherever you travel there may be a lizard around.
Like other reptiles, lizards are cold-blooded, but this has nothing to do with their temperament. They merely lack an internal heating system, so their body temperature is determined by their environment. As a result, those living in northern climates hibernate from late fall to early spring. If an area merely has chilly nights, a lizard will warm itself by basking in the sun until it’s ready to begin the day.
The vast majority of lizards dine on insects, bugs, and spiders, but larger species chow on bigger prey, such as mice. Whether they go after small flying objects or something larger, a lizard needs both speed and agility to catch a meal. Some species, however, prefer to eat plants.
Lizards’ long tails are handy when they are chasing down a meal or when fleeing a predator. A sharp jerk of the tail allows a lizard to veer toward and snatch an unsuspecting creature. When the tables are turned and the lizard is being chased, an abrupt change in direction can give it just enough time to avoid becoming another animal’s dinner.
Lizards aren’t particularly cuddly critters; most have skin covered with scales or plates. We typically get as close as our binoculars will take us. If you decide you need a really close-up view, be careful; most lizards come equipped with sharp claws.
The collared lizard that we saw in Arizona ranges north into Utah, east to Missouri, and southwest across Texas and New Mexico. Picture a lizard about one-third body and two-thirds tail and give it one or two black-and-white bands around the neck. Now cover the rest of the critter with colored dots — mostly brown shades, but with some orange to almost white spots. The collared lizards we saw had only a little bluish-green along the sides and belly, but one of our field guides has a photo of a lizard of the same species. Its brown head is accompanied by a bright-green body, legs, and tail. This lizard must live in greener surroundings.
As for other flashy attire, cross bands on the tail are common on lizards and come in a variety of colors and patterns. But the really eye-catching species are those with stripes that run from head to tail. Whiptails, especially, are stripe-prone. On one species, we counted as many as a dozen lines running front to back then gradually fading out down the tail.
Still, plenty of variety exists among striped species. The stripes of some are separated by a series of squares in a contrasting color.
You certainly get an idea of just how strange a lizard can be when viewing a Gila monster. Sleek and elegant it’s not. The entire body, head, and tail are a dirty pink decorated with black bands and complex patterns. Polka-dot-shaped bumps cover the entire body. All that, and they’re the only poisonous species found in the United States.
Lizards show a greater diversity in size, shape, color, and behavior than any other group of reptiles. Most have four legs and a long tail, but the burrowing lizard has either tiny legs or none at all. In fact, legless species look a lot like snakes. But like other lizards, they have eyelids and ear holes; snakes have neither.
A predator chasing a lizard may be disappointed if it grabs a lizard’s tail. Why? Because many lizards are able to release part or all of the tail when it’s grabbed, leaving the predator with a squirming tail while the rest of the lizard dashes to safety. The blood vessels once connected to the tail quickly seal to keep the lizard from losing too much blood. Over the course of several months, another tail grows in. The lizard will never resume its former elegance, though. The new tail has less color, and there is a “stump” where the new and old portions intersect. But hey, it’s better than becoming the main course of some predator’s next meal.