The whacky world of chameleons
Chameleons are one of the strangest reptiles on the planet, with many brilliant traits. They are like little aliens from another planet.
Chameleon changing
They change colour and patterns to communicate with other chameleons.
When danger comes their way, perhaps in the form of a cat, they will turn brown and make their body’s very skinny, stretch out their tails, accompanied by swaying their body backwards and forwards. They then perform a little dance that gives the illusion of a branch blowing in the breeze.
If nervous, they exhibit stronger patterns and colours. Very often flattening the body like a pancake to make them seem more significant, as though they are a larger and more dangerous creature.
Warming up and cooling down
Changing of colour is not just for communication; it regulates the body temperature (thermoregulation). Darker colours attract more warming sun rays and lighter colours reflect more heat, keeping the body cool. Flattening the body gives the sun a larger surface area to heat in contrast to a skinny body which attracts less energy, resulting in the sun hitting a smaller area allowing the chameleon to cool down.
How they change colour
This is evolution at its finest. Light travels in waves called wavelengths, each colour has a different distance between each wave. Chameleons take advantage of this with tiny nanocrystals embedded in their body which reflect light. When these crystals are far apart from one another, tension causes the skin to stretch, they show red, when the skin relaxes (red travels in longwave) a bit closer orange (shorter wave) and blue (shorter again). This is how they communicate with one another.
Vision
Unlike most animals we know Chameleons eyes move independently of each other. Capable of looking in two different directions at the same time with a 360-degree view of the world. They have binocular vision and can see a small insect 10 meters away, on top of that, they see in full colour and ultraviolet light (not visible to humans). The tiny little eyes are continually dashing up and down, side to side until they see an insect, then both eyes focus in unison and fire out the tongue with incredible accuracy.
Tongue
One and a half times the length of the body. The tongue muscles are incredibly powerful and at the end of its tongue is a sticky mucus some 400 times thicker than human saliva. This mucus is not normally very sticky until the chameleon fires out its tongue at high speed. I mean very fast; we are talking in some species 0-96.5 km (0-60mph) in an incredible 100th of a second with fantastic accuracy. At this speed, the tongue becomes incredibly sticky and latches onto the insect. The prey is then quickly pulled into the mouth to be crushed and swallowed.
Cask on chameleons
This is more pronounced on some species than others. The Yemen chameleon featured here in the pictures has a great example of a cask. It has a few applications, first to gather water. The droplets of moisture flow down the cask forming a little stream leading to the mouth. On dewy mornings the dew condenses into droplets and flows down to give a refreshing drink.
The cask is also a good way of attracting heat from the sun, thanks to its large surface area and blood supply it carries warmth to the rest of the body.
Males with a high cask are usually more dominant than males with shorter ones. It is seen as a sign of attractiveness and virility by females. The ladies prefer the fellas with the higher Cask.
