חוקי אבולוציה

The ability to see colors presents distinct selective advantages for species, such as being better able to recognize predators, food, and mates. Indeed, it is thought that simple sensory-neural mechanisms may selectively control general behaviour patterns, such as escape, foraging, and hiding. Many examples of wavelength-specific behaviour patterns have been identified, in two primary groups: less than 450 nm, associated with natural light sources, and greater than 450 nm, associated with reflected light sources.^[29] As opsin molecules were subtly fine-tuned to detect different wavelengths of light, at some point color vision developed when photoreceptor cells developed multiple pigments.^[20] As a chemical adaption rather than a mechanical one, this may have occurred at any of the early stages of the eye's evolution, and the capability may have disappeared and reappeared as organisms became predator or prey. Similarly, night and day vision emerged when receptors differentiated into rods and cones, respectively.

תוקן על ידי דייר ב- 18/10/2012 12:49:27