Do primates have color Vision like people do?

There is considerable variation between primates in terms of the ability to see colors. The best color vision exists in diurnal species. This is not surprising. Color sensitive cones would be of little use to nocturnal primates due to the fact that they require the relatively bright light of daytime to detect color. Humans, apes, and most, if not all, of the Old World monkeys are trichromatic (literally "three colors"). They have three different kinds of opsins on their cones which allows them to discriminate between blues, greens, and reds. In contrast, prosimians, such as lemurs and lorises, have relatively poor color vision being dichromatic. They can differentiate blues and greens but not reds. Color vision among New World primate species is surprisingly variable. Some of them are dichromatic and others are trichromatic. Most females in some species can distinguish reds but no males can. This is the case with marmosets, tamarins, squirrel and spider monkeys. All males of these species only see blues and greens. About 40% of the females apparently are also dichromatic, but the other 60% are trichromatic. Both male and female howler monkeys are trichromatic. At the other extreme, the nocturnal owl monkeys are monochromatic (literally "one color"). They see only black, white, and intermediate grays.