How Does the Human Eye Compare to the Eyes of Other Animals?

The human eye captures roughly 24 images per second. This means that if your eye were a camera, it could snap 24 pictures every second. This is why when you wave your hand in front of your face it appears blurry and translucent. How does this compare to other animals? Well, for starters, insects see about 250 images per second.

Vision

• Normal human vision is 20/20. In comparison, dog vision is between 20/50 and 20/100, horses are at about 20/33, and cats are at 20/100. (However, these number can vary significantly, because it is quite difficult to measure animal vision.)

Visual Acuity

• Because animals have less visual acuity than humans, they do not perceive things as sharply as humans do. Their vision could be likened to watching a blurry Internet video as opposed to watching television.

Color Vision

• Dogs perceive color almost like humans who are red-green colorblind. Both cats and dogs respond to blue and yellow best, and have trouble seeing shades of green and red. Cats perceive shades of red as black, and shades of green as white. To a cat, your front lawn looks like a textured bed sheet.

Sensitivity to Light

• Cats and dogs, unlike humans, have what is called a tapetum in the back of their eye that causes light to reflect back out of their eyes. Because of this, both dogs and cats can see much better than humans can see in the dark. Cats see about six times better than humans in the dark.

Field of View

• Horses have eyes similar to those of human beings, but they have a 350-degree field of view because their eyes are positioned on the sides of their heads. Humans can see only about 180 degrees.