What did we do?

We assumed that if dogs couldn't perceive color, they'd just see gray. So we scattered 15 gray tennis balls in the grass. We threw a new gray ball and told the dog to fetch it. We did this five times. That was our control test. Then we tested five other colors: blue, green, red, yellow, and pink. We threw each colored ball into the field of gray balls, and told the dogs to betch. Again, we did this test five times for each color. We wrote down how many times the dog retrieved the correct ball. We figured that if the dogs were colorblind, they'd have a hard time picking out the colored ball from the gray ones. more...