Dog's sense of sight

Dog's sense of sight: Though apparently not as highly defined as their sense of smell and hearing a dog's sense of sight is none the less powerful and very practical for these animals that rely heavily on their sight for their survival and which without their other senses would not function as powerfully as they do.It is very important that a puppy between the ages of zero and four weeks be exposed to people in many settings and occasions for the purpose of "imprinting". A dog that hasn't had these experiences at an early age can more easily develop phobias and fears about people, which will have a detrimental affect on its future behavior and trainability. Dogs have a two hundred and fifty degree field of vision that is about seventy degrees more than humans. And some breeds with elongated heads can even look at two different places at the same time. While tests have shown that dogs can spot a moving object at a distance of three hundred and fifty meters they can only spot stationary objects at a distance of about two hundred meters. Hunting dogs and herding dogs both have a more highly developed sense of sight and can generally discern movements at greater distances than other breeds. With their highly developed sense of sight dogs can easily spot even the slightest changes in the physical conduct and movements of their masters. It seems that while dogs are technically color blind they have such a strong ability to discern between shades that it seems sometimes that they can discern between colors. Seeing eye dogs, for example, cannot discern between the colors of the traffic lights and so use their other senses to decide when it is safe to cross. They listen to the movements of the traffic and watch the actions of the other pedestrians and then use this information to make their decisions. Dogs see better than humans in the dark because their pupils are able to open up wider than ours. This is why their eyes appear to shine when a light enters their eyes, it is reflecting on the ocular lenses in the backs of their eyes.