Colors are a complex phenomenon, some of which exist... some don't!
Those that do exist are an interpretation of our brain, and those that don't are a construction of the same brain!
Skeptical? Have you ever seen pink or white in a rainbow?
Then, by all means, a color....
A color is basically light of a certain wavelength. Or a mixture of lights of different wavelengths, all interpreted by our brain.
A beautiful explanation of the phenomenon, by David Louapre :
Light is composed of several frequencies (or wavelengths).
Even if you don't know Pink Floyd, you've already seen this:
Mixing all the colors (white) creates a beautiful rainbow!
This rainbow is the visible spectrum. The one our eyes can see.
But beware! We (humans) are not THE reference for the visible spectrum!
We mainly see 3 wavelengths:
The human eye does not react identically to different wavelengths:
It's not for nothing that color CRT screens had these 3 components! it's the one that the eye perceives best. The other colors are simply an interpretation by the brain: no wavelength makes "pink" or "white", it's the brain that interprets.
Animal eyes do not have the same characteristics: neither in shape, nor in constitution, nor in visible spectrum. We shouldn't draw conclusions about their visual faculties from our human vision.
| The animals | What they perceive |
|---|---|
| BIRDS(jumpers) | ULTRAVIOLET AND GREEN |
| INSECTES (bees) | ULTRAVIOLET, BLUE, AND YELLOW |
| CRUSTACES (crayfish) | BLUE AND RED |
| CEPHALOPODS (octopus and squid | BLUE |
| FISH | 2 COLORS |
| AMPHIBIANS (frogs) | SOME COLORS |
| REPTILES (snakes) | SOME COLORS AND INFRARED |
| BIRDS | 5 TO 7 COLORS |
| MAMMIFERES (cats) | 2 COLORS BUT WEAKLY |
| MAMMIFERES (dogs) | 2 COLORS BUT WEAKLY |
| MAMMIFERES (rabbits) | BLUE AND GREEN |
| MAMMIFERES (squirrels) | BLUE AND YELLOW |
| MAMMIFERES (gorillas and chimpanzees) | Like HUMANS |
| MAMMIFERES (African monkeys) | Like HUMANS |
| MAMMIFERES (South American monkeys) | They can't see red very well |
What suits us in terms of light won't necessarily suit them, and vice versa!
