Believe it or not, dogs can see more than just black and white. The color range they see, however, is limited compared to the colors humans see. Dogs see in yellows, blues, and purples rather than reds, greens and oranges. Next time your dog is fetching an orange ball thrown into green grass, remember he sees both the ball and the green grass as yellow.
What’s the reason? The eyes of both humans and dogs contain special light catching cells called cones. These cones respond to color. Dogs only have two cones while humans have three, making the colors dogs see less rich or less intense compared to humans.
If your dog runs right past that orange ball in the yard, it’s not because he’s being stubborn or silly, it’s because he might not be able to differentiate the color of the ball to the color of the grass. Try tossing a blue ball rather than an orange one, and see if your dog responds differently to the color of the ball.