How do Chameleons change colour?
The answer was found after the observation of the panther chameleon of Madagascar with a general name Furcifer pardalis, when the chameleon was changing its hue from green to vivid red within a few minutes. It was observed in a new perspective that, the lizards rely on structural changes that affect how light reflects off their skin.
THE STRUCTURAL CHANGE
Chameleon skin has an outer layer which contains thick layers of iridophores and chromatophores cells (that is, the first and second layers with pigment-containing and light-reflecting cells), and under the first layer, there are cells with nanocrystals of different sizes, shapes and organizations, which are key to the chameleon dramatic color shifts.
Therefore, Chameleons change colour by changing the space between the nanocrystals or changing the structure of the nanocrystals, which changes the wavelength of light reflected off the crystals and changes the colour of the skin.
HEAT SHIELD CRYSTALS
Also, there is a second deeper layer of iridophores that protects the chameleon from heat. “These cells, which contain larger and less ordered crystals, reflect a large amount of degree of the infrared wavelengths.
HOW DO THE CHAMELEON REARRANGES THE NANOCRYSTALS?
Perhaps, this question is still under deep research. Scientist are exploring the rearrangements of the nanocrystals.
HOW DOES THE CHAMELEON KNOW WHAT COLOUR TO CHANGE?
You will see a chameleon, it suddenly changes to like-background colour. How do chameleons know which colour is surrounding them? Do they see it with their eyes or are there some other receptors for that purpose in their body?
From research and observations, a chameleon may change it’s colour due to the mood of the chameleon. So if the chameleon is in direct sunlight it will become a lighter colour to reflect more heat, and when in a shade, it will become darker to absorb more heat. It just so happens that this means it will also be changing colour to better blend into that surroundings.
However, scientist are still working on the discovery of this wonders. New ideas and observations may be introduced as time goes on with their research.
These are the basic principles behind the change in colour of chameleons. As research goes on, we will discover more observations and know more about chameleons colour change.
This Post may frequently be updated.
