Mary Allen
Snakes recognize heat sources with their eyes. Birds of prey can spot mice from a distance of 500 meters. Flies see faster than we do. The television picture appears to them in slow motion, since they can process significantly more images per second than we humans. The vision of all animals is adapted to the environment and behavior, including our pets. In some ways they are superior to us, in others, we can do better.
Dogs are Nearsighted and Cannot See Green
Our four-legged companions have significantly more sticks in their eyes than we humans. This allows them to see well even in low light. If there is pitch darkness, they also feel in the dark. Unlike healthy people, dogs are nearsighted. The dog cannot see anything that is not moving and is more than six meters away from you. People, on the other hand, can see clearly even at a distance of 20 meters.
Color vision has never been related to dogs; However, as is often assumed, they are not color blind. Dogs can perceive certain colors, but not as many nuances as humans. We can recognize wavelengths in the range of red, green, and blue and thus about 200 colors. Dogs only have two types of cones and therefore mostly recognize blues, purples, yellows, and browns. Red tones seem yellowish to the dog, he does not recognize green at all.
Cats Have a Residual Light Amplifier
The eyes of our domestic cats are especially well adapted to see in the dark. Its pupils can dilate greatly, which means that enough light can still reach the retina. Behind the retina is also a reflective layer, the tapetum, a kind of residual light amplifier that transmits light through the retina again. This means that the light from the moon is enough for them to successfully hunt. More sticks also allow them to better recognize fast movements. We can perceive slower movements better than a cat. Our color vision is also more varied; to a domestic tiger, the world appears bluish and yellowish.
Horses Don’t Like Dark Colors
Horses’ eyes are located on the sides of the head. As a result, the field of view covers a very large radius – it has an almost all-around view. They also recognize enemies approaching from behind early on. It also helps that they are farsighted and see better into the distance than straight ahead. If you want to see an object more clearly, you need to turn your head so that you can look at the object with both eyes at the same time. The animal needs some time to do this, but this is not a disadvantage. Recognizing movement has always been more important for a fleeing animal than focusing on stationary objects.
Color vision in horses has not yet been fully explored. It is believed that they can mainly distinguish between yellow and blue. They don’t even recognize red and orange. Dark colors seem more dangerous than light colors; too light colors blind you. Like cats, horses have a special reflective layer in their eyes that greatly improves vision in the dark. They don’t like sharp transitions from light to dark. Then they become blind for a short time.
Farsighted and Red-Green-Blind Rabbits
For the rabbit, as a prey animal, a good all-around view is much more important than keen vision. Each eye can cover an area of approximately 170 degrees. However, they have a 10-degree blind spot right in front of their face; but can perceive the area through smell and touch.
At dusk and in the distance, the eared ones see very well and therefore quickly recognize their enemies. However, they see objects near them blurry. Therefore, rabbits are more likely to recognize people by smell or voice than by their appearance. Long-eared ears also lack a receptor, which limits their color vision. They do not have a cone receptor for shades of red, and they cannot distinguish this color from green.