howler monkey eating in a tree

Lizard Lifestyles

Many people have incorrect and unpleasant notions of lizards, so I like to show them how really lovely lizards are.

Posted in: Rainforest Connection Live

Some of my favorite animals are lizards. The best way to do this is to see lizards alive and firsthand in their natural habitat. But if we can’t do that, maybe this account and some photos will help.

Lizards often have rich, complex skin colors and textures: blended blues, greens, browns and tans. Some can change their colors, and we often call them chameleons. However, the name chameleon is for a special kind of lizard with mitten-like paws, tails that grasp and rotating eyes, that live only in Africa and Madagascar. There are many lizards besides chameleons that can change color, just not as wonderfully as true chameleons.

Lizard eyes are sharp and alert, sparkling, and some are flecked with gold. Their eyes are constantly surveying their surroundings, watching for prey or predators. People often call lizards cold-blooded, but I don’t understand why. A warm lizard is usually hotter than most mammals, and quicker at reacting. But a cool lizard is sluggish and sleepy and needs to stay hidden until it can bask in sunlight and get warm again. It’s fun to watch lizards waking up, becoming alert and active with tongue flicking, toes quivering, and eyes glancing around. If you can stay close-by quietly watching, you can see their little rib cages expand and contract as they breathe in and out. Some have such delicate bodies you can even see the movement of their hearts beating. As their bodies warm in the sun, they breathe faster and deeper, and their hearts beat more quickly. The faster they can breathe and circulate their blood, the faster their brains will work, their reflexes react, and their muscles move. That’s what they need to catch an insect for a meal or escape a predator like a bird or mammal.

Lizard predators include cats of all sorts, domestic or wild. Ocelots on BCI usually include lizards in their diet. Various birds of prey, especially double-toothed kites, like a lizard snack.

These kites are small hawks that travel with troops of white-faced monkeys. The monkeys search for food in the leaves of trees and under the bark of tree trunks. Their scrambling and searching is very noisy and rapid, scaring up many hiding insects and lizards. The kites watch from perches and dive in quickly when they see a running lizard or large insect. Some snakes feed on lizards, and so do coatimundis.

Just as lizards come in many colors, sizes, and shapes, they also have many different lifestyles to match their body differences. Some are long, slender, and fast-moving; others are wide-bodied and slower-moving. Some eat plants and others eat insects. Some are active in the daytime and others in the night-time. Some live on the ground and others in treetops. Some live in the forest and others live in buildings. Let’s look at some different kinds of lizards.

Green Iguanas and Ctenosaurs are big lizards that usually eat insects when young and then eat plants when they get older. Except that I have seen very big Ctenosaurs living next to a hamburger stand who ate hamburgers tossed to them on Manuel Antonio Beach in Costa Rica. The first Ctenosaur I ever saw was stretched out on a garden wall casually munching orange trumpet flowers while basking in the sun. Ctenosaurs usually like to live in old buildings, rock piles and cliffs, or road embankments. Green iguanas, however, like to live in the high, breezy tops of tall trees. Their long claws help them hang onto the branches. They come down to the ground to dig nests in the ground on sunny beaches and lay their eggs deep down where coatimundis can’t find them.

Many smaller species like anolis and ameivas, and basiliscus are insect-eaters all their lives. When lizards are small because they are young or just because their species is small, they can live on insects. They can move quickly and grab an insect and make a nutritious meal out of even a small bug. If the lizard grows very big, an insect isn’t much of a meal, and it takes too much energy to catch a fast-moving fly or beetle. So our bigger lizards have to do something different. Some become camouflaged predators that sit and wait for an insect to walk by, then the lizard dashes from a hiding place to catch it. The bigger iguanas feed on flowers, fruits, and tender leaves, which can’t run away at all. They need a special system to digest the plants, but that’s what they have.

Most lizards are active in daytime, but geckos are special. They wake up when other lizards are going to sleep.

Next time we’ll look at geckos.