Chameleons Up Close

Eyes, Tongue, and Tricks

A chameleon is a lizard, but it is one of the strangest lizards in the world. There are about two hundred kinds of chameleons, and most of them live in Africa and on the island of Madagascar, in forests, bushes, and dry grassland. They are best known for changing color, but that is only one of their odd talents. A chameleon has eyes that move on their own, a tongue like a stretching spring, and feet that grip like a pair of tongs. Most kinds spend nearly all of their lives climbing slowly through branches, and some are tiny while others are longer than a school ruler.

A chameleon's eyes sit on little cones that stick out from its head, and each eye can swivel on its own. One eye can look forward while the other looks backward, so a chameleon can see almost all the way around without turning its head. When it spots an insect, both eyes swing to the front and aim at the same target. That helps it judge exactly how far away the meal is. Its eyelids are joined into a single cap of skin, with only a small round hole in the middle for the eye to look through.

The tongue is the chameleon's most amazing tool. Folded up inside its mouth, it can be as long as the whole body of the animal, and in some small kinds it stretches to about twice the body length. It shoots out faster than you can blink. The tip is sticky and shaped like a tiny cup, so an insect sticks to it and is pulled back into the mouth. A chameleon never has to chase its food, because it simply waits on a branch, and the whole catch takes less than a second.

Color and Movement

Everyone knows that chameleons change color, but the real reason is not what most people think. They do not change to match whatever they sit on, like a magic cloak. Mostly they change color to send messages and to manage their temperature. A calm chameleon is often green or brown. An excited male can flash bright yellow, red, or blue to show off to females or to warn off a rival. A cool chameleon darkens its skin to soak up warmth from the sun, and a hot one turns paler to reflect the heat.

The color change happens in the skin. Special skin cells hold tiny crystals, and the crystals bounce light back to your eyes in different colors. When a chameleon is relaxed, the crystals sit close together and reflect blue and green light. When it gets excited, the skin stretches, the crystals move apart, and the skin reflects yellow and red light instead. Scientists in Switzerland worked this out in 2015. There are also cells that hold colored pigment, and they mix with the crystal colors, which is why one chameleon can show so many shades.

A chameleon's feet look like small mittens split in two. On each foot, the toes are joined into two bundles that point in opposite directions, so the foot wraps around a branch the way tongs wrap around a hot dog. Many chameleons also have a long tail that curls up like a spring and holds on to a twig like a fifth hand. They walk with a slow, rocking sway, as if they were a leaf moving in the wind. At night they turn pale and sleep on a branch, still gripping it tightly.

A chameleon has no ear openings at all, so you will never see one with ears. For a long time people thought chameleons could not hear, but tests have shown that they can pick up some low sounds. They are not much for talking, either. Many kinds hiss when they are bothered, but most of their messages are sent with color and by moving their bodies. Chameleons also spend most of their lives alone, and two of them that meet in the wild will often just stare at each other or flash their colors and then move away.

Sizes and Short Lives

Chameleons come in a wide range of sizes. The smallest known kind is a leaf chameleon from Madagascar, and it is only about two centimeters long, about as wide as your thumb, so a whole adult can sit on a fingertip. One of the largest is Oustalet's chameleon, also from Madagascar, which can grow to about sixty centimeters. That is longer than two school rulers laid end to end. Many of the biggest kinds can be brightly colored, and some have horns, crests, or flaps on their heads that make them look like tiny dinosaurs.

Chameleons eat mostly insects, such as crickets, grasshoppers, and flies. Some large kinds also eat leaves and fruit. In the wild, many chameleons do not drink from ponds. Instead they lick drops of rain and morning dew from the leaves around them. Because they move so slowly and wait so patiently, a chameleon uses very little energy, and it can go for a long time between meals. That is one reason chameleons can live in dry places where other animals of the same size would struggle to find enough food.

Most female chameleons lay eggs. She digs a hole in the ground, lays her eggs inside, covers them with soil, and leaves. The eggs may stay buried for many months before the babies hatch, and the babies can look after themselves from the first day. A few kinds do it differently. Jackson's chameleon, which lives in East Africa, gives birth to live babies instead of laying eggs. The males have three horns on their heads, just like the dinosaur Triceratops, and they use the horns to push against other males.

One chameleon has the shortest life of any four-legged animal that scientists know about. Labord's chameleon lives on Madagascar. It hatches from its egg when the rains begin in November, grows fast, finds a mate, and lays its eggs by about the end of February. Soon afterward, the adults die. That means the chameleon lives only about four or five months, and for most of every year the whole kind exists only as eggs hidden in the soil, waiting for the next rainy season. No other four-legged animal that scientists have studied lives such a short life.