Black and White

[Illuminati]

I've been told before that dogs see in black and white, however in light of recent evidence, I believe that some dogs see color (atleast in partial color).

 

My reason behind this is the other night, I was teasing the cat with a lazer pointer. My dog (who is lab/golden retreiver) had seen the lazer pointer and took chase with the cat. Now, as you can imagine, this was very comical, but thats beside the point.

 

The lazer pointer is red and not that much different in brightness from the carpet to the wall, however the dog chased it the entire time. I tried this on two other dogs and the others either ignored it or could not see it.

 

So, I came to the conclusion that this dog has the ability to see in color, this is completely against what I've been told in the past.

 

Could anyone shine a little light on this situation?

[Sayonara]

Seeing in black and white does not mean that the animal can only perceive black and white objects.

[Sisyphus]

My uncle is colorblind, and he loves his laser pointer. So apparently it's not at all difficult to see.

[bascule]

Dogs have dichromatic vision, meaning they only have two kinds of pigments in their retinas instead of three. Just because they're color blind (compared to us trichromats) doesn't mean they see in black and white. They can still see colors, just not all of the colors we can see:

 

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2487095&dopt=Abstract

 

The color vision of three domestic dogs was examined in a series of behavioral discrimination experiments. Measurements of increment-threshold spectral sensitivity functions and direct tests of color matching indicate that the dog retina contains two classes of cone photopigment. These two pigments are computed to have spectral peaks of about 429 nm and 555 nm. The results of the color vision tests are all consistent with the conclusion that dogs have dichromatic color vision.

[MindOfChaos]

I always thought dogs could see color just like we do. Now I know dogs have dichromatic color vision. Makes me see dogs in a slightly differen't light.

 

Is this how people become color blind? When one of these pigments is missing or damaged?

[Illuminati]

Seeing in black and white does not mean that the animal can only perceive black and white objects.

 

I meant more that dogs can see the objects, no matter the color, but in the case of the lazer pointer, being that the dot has no depth he wouldn't be able to see it against a backgrount of similar color seeing as the two would blend.

 

In any case, I'm basing these ideas off of the two other dogs I tried it on.

 

At any rate, thankyou for the clarification bascule.

[Steph]

I always thought dogs could see color just like we do. Now I know dogs have dichromatic color vision. Makes me see dogs in a slightly differen't light.

 

Is this how people become color blind? When one of these pigments is missing or damaged?

 

You have three kind of cells (cones) that detect light at a specific wavelength. So to have a color deficiency, you can have:

-Missing cell types (VERY rare)

-The peak wavelength that the cells are sensitve to are shifted, or you have decreased sensitivity. for some reason, insensitivity to blue light is also rare.

[Glider]

It wouldn't really matter whether or not dogs only had monochromatic vision. The laser point would still appear as a very bright (and moving) point of contrast against the background.

 

If you have a digital camera, take a black & white photo of a laser point on a wall, you'll see what I mean.