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From velvety purples to fiery reds, many people can see a spectrum of vivid colors via the human eye. Others, however, may have limited hue perception due to certain conditions.. Animals, on the ...
A cat's visual acuity is anywhere from 20/100 to 20/200, which means a cat has to be at 6 metres to see what an average human can see at 20 or 30 metres. Cats seem to be nearsighted, which means they cannot see far objects as well. The ability to see close objects would be well-suited for hunting and capturing prey. [2]
Trichromatic color vision is the ability of humans and some other animals to see different colors, mediated by interactions among three types of color-sensing cone cells. The trichromatic color theory began in the 18th century, when Thomas Young proposed that color vision was a result of three different photoreceptor cells .
The basis for this variation is the number of cone types that differ between species. Mammals, in general, have a color vision of a limited type, and usually have red–green color blindness, with only two types of cones. Humans, some primates, and some marsupials see an extended range of colors, but only by comparison with other mammals.
Such findings may give an evolutionary reason for the high rate of red–green color blindness. [18] There is also a study suggesting that people with some types of color blindness can distinguish colors that people with normal color vision are not able to distinguish. [17] In World War II, color blind observers were used to penetrate camouflage.
Mammals other than primates generally have less effective two-receptor color perception systems, allowing only dichromatic color vision; marine mammals have only a single cone type and are thus monochromats. Honey- and bumblebees have trichromatic color vision, which is insensitive to red but sensitive in ultraviolet to a color called bee purple.
Blind cats make wonderful pets, just take Coraline! But they do need very special care. Because they can't see, you'll want to keep your blind cat indoors so they stay safe. If you do let them ...
Dichromacy in humans is a form of color blindness (color vision deficiency). Normal human color vision is trichromatic, so dichromacy is achieved by losing functionality of one of the three cone cells. The classification of human dichromacy depends on which cone is missing: Protanopia is a severe form of red-green color blindness, in which the ...