Can Animals Truly See in Black and White?

[mapper]

They say animals like cats, dogs etc.. don't see colors. Their world is in black and white. How on Earth can they be certain about this? How can one test this or even set up an experiment to test this and form a conclusion based and any of the results?

 

[Almeisan]

One can make a test and reward them if they see the difference between colours.

But they do not see in black-white. Humans see in three colours. Most mammals see two colours.

I cannot give examples and results of actual tests being done.

 

[Monique]

Yes, take two colors whose intensities are the same, so that they would look the same in gray, and see whether you can condition the animals to associate food to one of the colors.

For instance: you make a button that can change color. When it is green the animal will get food, when it is red the animal won't get anything. The animal should learn to only push the button when it is green, when it does this it can see color.

You should ALSO do a control experiment, to make sure that the animal is able to learn such behaviour at all (otherwise you get false negatives). You make the button in two shades of grey. Assuming that the two contrasts are distinguishable for the animal, it should learn to only push the button when it is one of the shades.

 

[Monique]

Humans see in three colours.

Not entirely correct, but it is true that we have three types of cone pigments: red-sensitive, green-sensitive and blue-sensitive. As you can see in the graph on this page http://science.howstuffworks.com/eye3.htm, the sensitivities of the pigments overlap: the eye can see almost any gradation of color between the peaks.

 

[matthyaouw]

Do animals also lack cone cells in their retina? I'd think that would be a reasonable indicator.