How EYE 👀 see it: Animal vs. Human eyes - Part 1

"Vision is the art of seeing what is invisible to others- Jonathan Swift"

Do Animals see things and colors that we can not see? Or is it vice versa?

Ever wonder how the world looks through Animal eyes?

(Composite made by me with my original photos)


While looking at some of my close up animal and bird shots, the variations in their eyes piqued my interest and I started looking up the capabilities their eyes. I am going to share what I learnt, in this blog. This is Part One of the blog covering Cats (Like Tigers and house cats) and Dragonflies.

The structure of the eye in each species, including Humans, is different. The structure dictates the range of vision in terms of:

• Distance up to which objects can be seen clearly
• Color range that can be perceived
• Lowest light threshold levels under which the eye can see clearly
  &
• Field of vision.

How the final image is perceived by the brain is also dependent on the structure of the eye.

Let us take a look at some of the animal kingdom eye capabilities.

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Cats (large predatory cats & even house cats) have more rods in their retina than cones. This dramatically increases their ability to see at night and sense movement but reduces their perception of color range. This evolutionary development helps them with their lifestyle, which depends on hunting at night. Their prey, typically can not see as well as them, at night!

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The upper picture represents what we would see and the lower one represents what the cats would see. Cats have a higher field of vision (Almost 200 deg. angle) but they can see much lower range of colors. The universe certainly looks dull to them compared to us.

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The upper picture represents what we would see and the lower one represents what the cats would see. Cats have a threshold of light lower by 7 times compared to humans and hence can see much better

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Dragonflies have compound eyes which are fixed (can not swivel like humans) but are made up of 30,000 tiny lenses - each lens looking in a different direction. The brain then makes a composite picture from inputs of all 30,000 eyes.

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Dragon flies can sense a very low range of color compared to the human eye but they can see ultraviolet range of light. This dramatically alters the picture that they see and makes it easy for them to identify prey.

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Though they have 30,000 lenses, each of the lenses is about 100 times less in quality compared to human eyes. The composite formed in their brains is badly pixelated. Therefore, dragonflies see much less detail than human

With these examples, isn't it obvious that we, the humans, do have a great pair of eyes but the animals beat us on some counts?

With our changing life styles, do you think we need to evolve to get some night vision or ultraviolet capability?

How about some automatic computer glare protection? Please share your views.

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