Orange (colour) Orange (colour) Orange is the colour between yellow and red on the spectrum of visible light. Human eyes perceive orange when observing light with a dominant wavelength between roughly 585 and 620 nanometres. In painting and traditional colour theory, it is a secondary colour of pigments, created by mixing yellow and red. It is named after the fruit of the same name. The orange colour of carrots, pumpkins, sweet potatoes, oranges, and many other fruits and vegetables comes from carotenes, a type of photosynthetic pigment. These pigments convert the light energy that the plants absorb from the sun into chemical
Evolution of human colour vision allow them to see a wider range of the electromagnetic spectrum. Secondly, new random connections would create wavelength opponency and the new wavelength opponent neurons would be much more sensitive than the non-wavelength opponent neurons.This is the result of some wavelength distributions favouring excitation instead of inhibition. Both excitation and inhibition would be features of a neural substrate during the formation of a second pigment. Overall, the advantage gained from increased sensitivity with wavelength opponency would open up opportunities for future exploitation by mutations and even further improvement. Evolution of human colour vision Evolution of human colour vision over time: