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- What color is the world that animals see?
What color is the world that animals see?
- TAG
- Vision
How good is the vision of cats and dogs?
Do they see in color?
What does our ordinary world look like to other animals?
We humans use our two eyes to see the world around us. Two important features of our sense of vision are that we can see in three dimensions and in full color. But have you ever wondered how dogs and cats or other animals see the world? When you observe your own pet, you probably sometimes scratch your head in doubt and think, “Does she really notice this?” How do animals grasp the world?
To begin with dogs, they are actually quite shortsighted with an eyesight of only about 0.3. Their ability to discern colors also lags behind us humans, and it is believed that they see the world in a rather blurry monochrome (although some recent researches suggest that they may have a faint sense of color after all). On the other hand, their capacity for seeing movements is outstanding and their ability to grasp quickly moving object is far beyond that of humans. Their field of vision is 220 – 290 degrees, which also makes them much better at detecting dangers. (The human field of vision is only about 180 degrees.)
Cats are famous for their ability to see clearly even when it’s dark. If you examine the eye of a cat, it not only has a larger number of photoreceptor cells than a human eye, it also has a reflecting layer called the tapetum lucidum or “eyeshine” behind the retina, which recycles some of the light back to the photoreceptors. Cats’ eyesight, however, is not as good as humans’, and while they seem to be able to tell the difference between blue and green, red is apparently impossible.
Birds, on the other hand, have far superior vision than humans. Eagles and falcons, for example, are said to possess an eyesight 8 to 10 times more acute than humans, which enables them to discover and swoop down on tiny animals on the ground. Some people have the idea that birds are night-blind, but nothing could be further from the truth. Birds’ vision does not deteriorate at night, and in fact many migrating birds fly long distances at night.
All this has been about how animals grasp the world around them using their vision, but we mustn’t forget that animals also have a much better sense of smell and of hearing than we do, and that they use all their senses comprehensively. If a dog can recognize his owner by her smell, it doesn’t matter if he is shortsighted. Even if they can’t see faraway objects, animals have the ability to perceive dangers by their sound. While animals use all their senses fully to gather information about their surroundings, humans rely to some 80% on visual information. I’m not suggesting that from now on, we should train ourselves to distinguish each other by our smells, but perhaps it’s time to look a little closer at all of our senses.
