I've heard they put food behind a certain color door. After the animal had been trained to go to that door, they start throwing in other colors and shades of gray for the animal to choose between to see if they can tell the difference. If they go to the wrong door, they are probably colorblind. ... Something like that.
This post was edited by CallMeIshmael at October 25, 2018 8:05 AM MDT
"No" ... dogs are not colorblind in the sense that they see more than just black, white, and gray. However, the color range they perceive is limited compared to the spectrum we see. To put it in very basic terms, the canine color field consists mostly of yellows, blues, and violets.
Basically ... dogs can see colors that are bright (to us). Because dogs have more "black and white" receptors than humans ... and fewer "color" receptors. A bright red ball to us, looks like a dull reddish brown to them.
Which is also why they see better in low light.
EDIT: You can't really say they are "colorblind", though. Unless you want to also say that ALL male humans are "colorblind", because we aren't tetrachromatic.
This post was edited by Walt O'Reagun at October 25, 2018 10:58 AM MDT
To see in full colour as we know it, humans use three cones – red, blue and green. However cats and dogs only have blue and green cones. This means they have a much more muted perception of colour, which is akin to colour blindness in humans. SOURCE: https://theteacupdog.com/
