We are all a product of our evolution. Dogs evolved in a setting that required them to hunt in packs in daylight and at night. They used scent more than vision to find prey and were required to interpret body posture within the pack to establish a hierarchy. They did not require detailed or color vision to survive and therefore those traits were not selected for. However, studies show that dogs do see some colors. Their vision is thought to be divided into two hues, blue-violet and green-yellow. Dogs are unable to see orange-red hues. We can say that their vision most closely resembles human red-green color blindness. Keep that in mind the next time you go to the store and let your dog choose his or her new duds!