Why can dogs only see in black and white?

Question

Dont the do that all there lifes?

Answer 1

Scientists believe that canines can see part of the range of colors in the visible spectrum. Humans like you can see all the colors--red, orange, yellow, green, blue, indigo, violet--but dogs probably see mostly in shades of yellow and blue. But remember, this is only a THEORY, since we can't really find out if a color appears the same way to dogs as it does to people.

Two types of photoreceptor cells in the retina -- rods and cones -- respond to light and transmit electric impulses to the optic nerve through a series of chemical reactions. Rods process visual information in dim light and are sensitive motion detectors, while cones handle color and detail. The human retina contains approximately 100 million rods and 7 million cones.

Cone cells contain pigments that perceive specific wavelengths of color. Human vision is trichromatic -- we have three types of cones that recognize different portions of the color spectrum. These cones allow us to see a range of colors that are a mix of red, blue, and green pigments. Dogs have only two types of cones -- their dichromatic color vision is similar to that of a human with red-green color-blindness. In addition, a dog's retina contains a much smaller ratio of cones to rods than ours does.


Before you start feeling sorry for them remember that they have night vision far superior to ours.

Answer 2

Nope! Scientists believe that canines can see part of the range of colors in the visible spectrum. Humans like you can see all the colors--red, orange, yellow, green, blue, indigo, violet--but dogs probably see mostly in shades of yellow and blue. But remember, this is only a THEORY, since we can't really find out if a color appears the same way to dogs as it does to people.

The simple explanation for these differences in color vision is this. The retinas of normal humans have three (3) types of color receptors, called "cones". Each cone type is particularly sensitive to light of a narrow limit within the entire VIBGYOR range. That means that three different "cone lines" of communication run back to the visual part of the brain, which then compares the weight of the signals coming in from each of cone "line". Different weights produce a perception of different colors. In dogs (and in "green-blind" humans), there are only two (2) types of cones, so there is less basis for comparison by the brain, and thus the perceived color range is more limited. In sum, dog color vision is "color-limited", not "color-blind".

Answer 3

Who says dogs are color blind? For example, how can a guide dog for the blind distinguish a green light to lead his master safely across the street from a yellow caution light, or a red stop light if he is color blind? This would meand that the dog is acting on a monkey see, monkey do senario. What if the people were all jaywaking?

Answer 4

I've always wondered how we can prove they only see black and white. I guess that's why they say cats and dogs can see ghosts so much better than we can....

Answer 5

See there are these things in your eyes called rods and cones...cones let you see color. There is a big absence of cones in a dogs eye, therefore letting them see in black and white.

Answer 6

how do u no they could only see black n white

Answer 7

Actually they do not see in black and white. They see more of the green spectrum of light. That's why they see so well at night.

Answer 8

yes they can only see black and white all their lives

Answer 9

Yes

Answer 10

How do you know that they only see in black and white?????