Colour in Nature
Colour, in common terms, refers to the aspect of a visual experience generated by the sight of an object. In reality colour is not far from this description, it is the way an intensity of light absorbed, reflected, refracted, scattered and/or diffracted by a matter is perceived by the brain via a visual organ. Visible light can be described as part of the electromagnetic spectrum from 380 to 740 nm; the shortest wavelengths appear violet, while the longest appear red. In view of the fact that no wavelength of light is endowed with a colour, it is clear that colour appearance is a mental not a physical phenomenon. This becomes more apparent when analysing the evolution of colour in visually displayed regions of animals or plants and their correlations with advances in sensory organs destined for vision in their counterpart animals, as though it were a weaponry race. It is important to note that not all sensory systems are prepared to perceive the same range of wavelengths from the electromagnetic spectrum, for instance, insects perceive additional wavelengths that the human eye is incapable to perceive; from 300 to 700 nm, including the ultraviolet range. Colour in animals is achieved through two separate pathways; chemical and structural colour, notwithstanding these frequently act in combination to create further colourations and other light-interaction properties such as iridescences
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