Are dogs really color blind? and if they are how did we discover?

Question

because i have always wondered if they were color blind, then i thought how did we find out.

Answer 1

What I read was dogs do see color, just not as sharply as we do. I think it has something to do with the number of cones and rods the eye has.




Answer
Dogs are primed to see "motion." Rather than defining the world through sight alone. They use a blend of senses such as smell and hearing with their vision to do what we humans use our eyes alone to do.

That being said, they do have some color vision, but as the first answer said, just not as sharp as some humans, but NOT ALL humans.

There are millions of human beings who probably have a good approximation of "dog color vision" but we don't say that, we just say they suffer from some sort of "color blindness."

Just as there is a range in the human ability to see color (some humans have NO color vision at all - though it's rare) so too is it sensible to think that there are a fair share of dogs whose color vision is dramatically better than average and so too the opposite.

So yes there could be some people like the person below whose dog sees color every bit as crisply as we do.

The notion that dogs do not have color vision was rooted in some lazy early optical research studies done back in the early twentieth century, well before the actual function of a rod and cone in the retina was fully understood.

Thanks to that faulty understanding, because a dog's retina did not look identical to a human's who could see full color the researchers were too too quick to assume that dogs simply do not see color at all.

It's only recently that the question was revisted, and upon doing so the early errors and incorrect assumptions found and corrected.

Answer 2

Not necessarily true as it is said that dogs can SEE color, but not as humans do. For many years it was believed that dogs are color blind that they lived in a totally BLACK and WHITE world. Some research found that that's not the case,but it appears to be that color is NOT particularly important to them.

The ratio of rods to cones on the retina of the eye of the DOGS favors the RODS much more than humans. RODS are useful for black and white vision in dim light while CONES are employed in
color vision.

The "ROD-RICH" eyes of dogs are therefore specially adapted to a daily cycle which favours dawn and dusk as the periods of major activity (called a crepuscular rhythm), and is the typical mode for the majority of mammals.

The small number of cones in the eyes of dogs reveals that, although they
may not revel in technicolour excitements they human way, they must be
able to see at least some degree of coloration.

An eye-expert Gordon Walls said: "Any such seminocturnal, rod-rich animal (such as a dog), the richest of spectral lights
could at best appear only as DELICATE PASTEL TINTS of uncertain identity."
Such pastel tints appears to let them have some degree of color appreciation.

Simply put, dogs are not necessarily color-blind but they do have very poor color vision.

How do we know that? Theories are made out of experiments and tests done by some researchers.

Answer 3

There is a dog section under pets, and this question is asked all the time.

Dogs are not color blind.
There are scientists who go through many years of schooling to get their master's degree to study things like this.
Eyes have rods and cones. Cones allow color vision.
Humans have three types of cones. Dogs only have two. This means they see color, but not all of the colors we see.
Dogs see the world like a person with red-green colorblindness. They see the color blue best, but to dogs, colors are more muted, more pastel.

Answer 4

From 'The Straight Dope'

Three scientists at the University of California at Santa Barbara adopted the traditional strategy of trying to tempt the dogs with food. The menu, frankly, could have stood some improvement: would YOU cooperate with people whose idea of a reward was a cheese-and-beef-flavored pellet? Nonetheless, the researchers found three mutts who were sufficiently desperate to play along. They showed the dogs three screens lit up from behind with colored lights--two of one color, the third of a different color. The mutts got the pellet if they poked the odd-colored screen with their noses.

The dogs had no difficulty distinguishing colors at the opposite ends of the visible spectrum, such as red and blue, and they proved to be demons with blues in general, quickly learning to differentiate blue from violet. But they bombed at other colors, confusing greenish-yellow, orange, and red.

The researchers concluded that dogs suffer from a type of colorblindness that in humans is called deuteranopia. Normal humans have three types of color receptors for red, green, and blue. Deuteranopes lack the green receptor, and thus (apparently) can't tell a lemon from a lime--or, for that matter, a red traffic light from a green one. One more reason to put your foot down next time the pooch says he wants to drive.