The eyes transmit data and the brain interprets this into information and then renders the information as vision. What we see is a product of the brains. The image delivered by our eyes is not the same thing we "see" with our brain. Otherwise, we could not "see" when we dream.

We see color because the color contains important information. Most mammals, including most large, ground dwelling prey animals, do not see green very well if at all.

"While their Triassic ancestors were trichromatic, placental mammals are as a rule dichromatic; the ability to see long wavelengths (and thus separate green and red) was lost in the ancestor of placental mammals." http://en.wikipedia.org/wiki/Dichromacy

If prey animals used green as a way to better see predators, it would amost certainly be selected for and would exist. Evolution does not choose which colors to see based on how much information the colors contain, in and of themselves. We choose which colors to see based on their relevance to our survival. Most prey animals have relatively good motion detection (rod cells) to detect predatory movement. If they lost this ability, they would be much easier prey.

We developed the ability to see green when we lived in trees, as small primates millions of years ago. http://en.wikipedia.org/wiki/Evolution_of_color_vi... The abiliity to see ground predators probably made little if any difference in our preference to see green, since it was not meaningful for our survival.

"The exceptions to dichromatic vision in placental mammals are primates closely related to humans, which are usually trichromats, and sea mammals (both pinnipeds and cetaceans) which are cone monochromats. New World Monkeys are a partial exception: in most species, males are dichromats, and about 60% of females are trichromats, but the owl monkeys are cone monochromats, and both sexes of howler monkeys are trichromats." http://en.wikipedia.org/wiki/Dichromacy

Sea mammals don't need to see most color as it's not important to their survival. Vision is often useless in water, as conditions are bad or light is not available. They use sonar as an alternate way of seeing. The information that is seen through sound is very relevant to their survival, as sonar is effective in almost all aquatic environments. Owl Monkeys are nocuturnal and don't see colors at all. There is no need. They lost the ability to see color for through the same mechanism that most primates gained the ability to see color : if the color was necessary for our survival, it was selected for in our genes. If not, the ability to see color can break with little consequence (color blindness in humans), and could eventually be lost again.

Unusual among the New World monkeys, they are monochromats, that is, they have no colour vision, presumably because it is of no advantage given their nocturnal habits. They have a better spatial resolution at low light levels than other primates, which contributes to their ability to capture insects and move at night. http://en.wikipedia.org/wiki/Night_monkey

Wikipedia, "Research indicates that trichromacy allows animals to distinguish red fruit and young leaves from other vegetation that is not beneficial to their survival.[8] Another theory is that detecting skin flushing and thereby mood may have influenced the development of primate trichromate vision." http://en.wikipedia.org/wiki/Trichromacy