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Hello everyone.
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As you all know, eyes provide organisms vision, the ability to process visual detail, as well
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as enabling several photo response functions that are independent of vision.
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As you are watching this video, have you ever considered how this video would look like
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if you were a cat?
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Well, in this video, we are going to look at how the internet's favorite subject sees
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the world.
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The biggest difference between human vision and cat vision is in the retina, a layer of
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tissue at the back of the eye that contains cells called photoreceptors.
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The photoreceptors convert light rays into electrical signals, which are processed by
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nerve cells, sent to the brain, and translated into the images we see.
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The two types of photoreceptor cells are known as rods and cones.
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Rods are responsible for peripheral and night vision, where they detect brightness and shades
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of gray.
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Meanwhile, cones are responsible for day vision and color perception.
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To put it in simpler words, you see a lot of colors if you have a lot of cones.
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And you can see better in the dark if you have a lot of rods.
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Cats actually have a high concentration of rod receptors and a low concentration of cone
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receptors.
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Humans have the opposite, which is why we can't see as well at night but can detect
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colors better.
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Now let's take a look at the visual field.
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This refers to the area that can been when the eyes focus on a single point.
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It includes what can be seen straight ahead, as well as above, below, and to the side.
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As you can see, cats have a slighter wider visual field of 200 degrees compared to the
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average human visual field of 180 degrees.
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But, in the aspect of visual acuitty, which is the clearness of vision, the average human
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has a visual acuity of 20/20.
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A cat's visual acuity is anywhere from 20/100 to 20/200, which means a cat has to be at
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20 feet to see what an average human can see at 100 or 200 feet.
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This is the reason why cats seem to be nearsighted, which means they can't see far objects really
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well.
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The ability to see close objects would be well-suited for hunting and capturing prey.
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As you probably already noticed, the way cats see colors is also quite different from humans.
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It's a common misconception that cats can't see any colors, only shades of gray.
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Humans are known as trichromats, meaning they have three kinds of cones that allow them
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to see red, green, and blue.
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Cats are also thought to be trichromats, but not in the same way that humans are.
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A cat's vision is similar to a human who is color blind.
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They can see shades of blue and green, but reds and pinks can be confusing.
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These may appear more green, while purple can look like another shade of blue.
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Other than that, cats also don't see the same richness of hues and saturation of colors
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that we can.
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Even theough cats can't see fine detail or rich color, but they actually have a superior
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ability to see in the dark because of the high number of rods in their retina that are
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sensitive to dim light.
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As a result, cats can see using roughly one-sixth the amount light that people need.
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Cats also have a structure behind the retina, called the tapetum, that is thought to improve
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night vision.
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Cells in the tapetum act like a mirror, reflecting light that passes between the rods and the
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cones back to the photoreceptors and giving them another chance to pick up the small amount
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of light available at night.
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This is what makes cats' eyes glow in the dark.