|MadSci Network: Zoology|
Your question about chamelions is a clever one if you believe that they change colour to camouflage themselves. Chamelions are truly amazing animals for many reasons, but they are best known for their ability to change colour.
Actually, chamelions do not change colour to camouflage themselves. If you were in Africa you might be able to demonstrate this by picking up a chameleon and moving it from one plant to another. Just touching a chameleon can make it change colour. Most chameleons are green or brown and keep within this range of colours. They will change their colour over the course of several minutes according to their mood and light intensity.
I have seen chameleons disturbed by human beings which turned bright yellow. Now at night they are still within their normal colour range and you would see this if you were to shine a torch on them.
I have seen chameleons which were grey and extremely well camouflaged on rock but if I had moved these chameleons to an unusual habitat they would not have been able to change colour enough to remain hidden. Many chameleons are well camouflaged because their natural range of colours happens to suit the typical background that they would hang out in.
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