Vision & Hearing Capabilities of Dogs and Cats

We gauge our vision in a number of ways: ability to see color, detail, movement, depth of field and night vision. Like human eyes, canine eyes have rods and cones, but they have less cones than us and cones are responsible for color perception. In fact, dogs are considered red-green blind. They see more yellowish, white and various shades of blue. As far as detail is concerned, it is estimated that they have 6 times poorer detail vision than the average human. However, dogs have more rods and that gives them superior night vision, estimated 4 x better than us. A dogs sense of motion is also much better than ours. They can spot movement ½ mile away but can not see properly up-close, less than 1 foot in front of their nose, unless there is movement. In general, the longer the nose of the dog, the greater the field of vision. For example, the peripheral vision of a labrador is better than a pug. Cats are more like dogs than humans and are neither nearsighted or farsighted. But, cat pupils are unique. Their pupils can dilate to round quickly and let in a lot of light. They can see light at eight times dimmer illumination than a human. Their pupils can constrict into a slit also very quickly which allows good vision in daytime and night time, even better than a dog. But, cats eyes lose good focus and as such have detail deficiencies. They also have red-green color blindness, like dogs, and see more yellows, white and blues. The cat’s eye is more specialized to see in rapidly changing light which assists in their hunting ability, and they also depend much more on movement than up close focusing. As far as our pets hearing is concerned, both dogs and cats hear better than us, especially in the upper ranges. In fact, cats can hear almost one octave higher than dogs, and both can hear in the ultrasound level. Because of the shape of their ears and their ability to move them, cats and dogs can “funnel” sounds into their ears. In fact, depending on the breed, dogs have 18 or more muscles to control ear movement, and cats have many more than that, closer to 33 muscles, and cats can move each ear independently. Our pets basically live in a world much different than ours and fortunately with their intelligence, trainability, and astute hearing and vision, many of these wonderful attributes help mankind, especially in search and rescue missions, and helping the handicapped, for example.