There are those who are “cat people.” They love everything
that is feline and frequently have one (or more) cats as pets. Then there are
those who are allergic to cats (so most likely don’t own one – or more).
Whatever one’s opinion (love ‘em or leave ‘em) of cats, no
one can deny their general aura of cool sleekness. Part of that comes from the
slinky, sashaying walk that many have. The other comes from their eyes. In the
animal kingdom, cats’ eyes run the gamut of being the most expressive, from wide-eyed
and curious to pure
attitude of “you lookin’ at me?” arrogance. And while they have human-like
expressions (and feelings), we at Site for Sore Eyes wondered what (if any)
differences there were between how a cat sees the world and how human beings
see the world.
We recently checked out an archived article on “Business
Insider” titled “How
Cats See the World Compared to Humans.” With insight from Kerry L. Ketring,
DVM, DACVO of All Animal Eye Clinic, Dr. DJ Haeussler of The Animal Eye
Institute and the Ophthalmology group
at Penn Vet, author Dina Spector crystallized what the differences are in human
vision versus the vision of cats (and dogs for that matter). It all boils down
to the retina…
The retina,
generally speaking, is a layer of tissue at the back of the eye. The retina
contains what are called “photoreceptors” which convert light rays into
electrical signals, which then get processed by nerve cells that are sent to
the brain, thus “translating” and making the connection with what we see –be
it a person, pet, building, or anything else. The cells inside the
photoreceptor cones are rods (for peripheral and night vision, as well as
detecting brightness and shades of gray) and cones (for color perception and
day vision).
Now for what makes
the two different species see things differently. Quite simply, cats and dogs
have high concentrations of rod (but low) cone receptors. (This means they can
see REALLY well at night but are limited in how they perceive color.) Humans
have high concentrations of cone (but low) rod receptors. (That’s why night
vision goggles were only made for us, and we make a fuss over colors of the
cars we buy and how to paint our homes, among other frustrations.)
Other differences,
in a nutshell, are that cats have a wider visual field (200 degrees) compared
to humans (180 degrees). We can see things 100 feet away, but a cat has to be a
lot closer (20 feet away) to see the same object. This means that cats are also
by nature nearsighted, whereas we humans can be nearsighted, farsighted, or
somewhere in between.
Well, we hope you
have enjoyed this bit of a diversion of our usual type of topic. We hope you
cat lovers enjoyed this blog, and will share it with your fellow “cat fans,”
and have a new point-of-view (pardon the pun) for your feline family members.
We close with a blast-from-the past trailer for the movie “Stephen King’s ‘Cat’s Eye’”
which we are sure you have seen and may be part of your collection. If not,
check it out. The hero is a cat who finds himself in some bizarre and
mysterious adventures. Enjoy!
Thanks for reading… keep your sites (and those of your cat) on
healthy vision.
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