Dogs can see in color, on a blue and yellow scale, based upon this article on the Internet:
Scientist Jay Neitz from the American university carried out experiments on dogs to test whether they could see in colour or not.
He discovered that while human eyes have three 'cones' that detect colour and can identify red, blue, green and yellow light; dogs only have two.
This means dogs can distinguish blue and yellow, but not red and green.
The Russian scientists therefore printed four pieces of paper in different colours; dark yellow, dark blue, light yellow and light blue.
The dark and light hues were used to test the theory that dogs use brightness levels to distinguish between items.
In the first test, researchers took a dark yellow and light blue sheet of paper, as well as a dark blue and light yellow combination and put them in front of food bowls placed inside locked boxes.
They then unlocked one of the boxes and put the dark yellow piece of paper in front of the box containing a piece of raw meat in each trial.
Each test involved the dogs being allowed to try to open one box before being taken away.
