CHAMELEON

How Does A Chameleon Change Colour?
         The chameleon is constantly changing its colour. Camouflaging is a process which allows a certain creature or element to blend in with the surroundings. Contrary to popular belief, this change of colour is not only an adaptation to the surroundings but also an expression of the physical and psychological condition of the lizard. The skin colour also pays an important part in communication and rivalry fights.

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How Does A Chameleon Change Colour?
        Chameleons have specialised cells that lie in two layers under its transport outer skin. The cells in the upper layer, which are called chromatophores, contain yellow and red pigments. Below these chromatophores is another cell layer. Cells of the layer are called guanophores and they contain the colourless crystalline substance "guanin". These guanophores reflect amongst others the blue part of incident light.  If the upper  layer of chromatophores is yellow, the reflected light becomes green (blue +yellow). A layer of dark melanin containing melanophores is situated even deeper under this blue and white light reflecting guanophores. These melanophores influence the lightness of the reflected light. The approximate time for a colour change is about 20 seconds.

Why Does This Happen?
         Chromatophores change because they get a message from the brain. The message tells the cells to enlarge or to shrink. These actions cause cell pigments to mix- just like paint. A chemical called melanin also helps chameleons turn colour. Melanin fibres can spread like spider webs through layers of pigment.

PANTHER CHAMELEON WHEN HE IS ANGRY

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What Factors Influence These Colour Changes?
        Chameleons change colour to blend in with their surroundings besides helping them to communicate better among their species.
LIGHT:- Say when a brown chameleon decides to rest in the sun, its brain will send a message to tell the yellow cells to enlarge than the blue cells. This combination of shades turns the chameleon green. This lighter colour helps the skin reflect bright sunlight.
TEMPERATURE:- Suppose if a chameleon is cold, it might turn a darker colour. Because, dark colour absorb more heat than light ones. Thus it can survive in cold conditions with its sweater shield.
MOOD:- Varying moods cause most changes in a chameleon. E.g if a panther chameleon gets angry, red and yellow replace its normal colours. A chemical called melanin  rises toward the skin's surface, causing areas of the skin to darken.
        Thus a chameleon can easily blend in its surroundings with its very own nature given its power of colours!