Nomilynn
10-29-2002, 06:34 PM
More interesting cat stuff :D
--THE "EYES" HAVE IT - WHAT'S BEHIND THE CAT'S GLOWING EYES?
Your cat's unusually large eyes are probably her most
striking feature, and even more so at night. Since
the cat is a nocturnal creature, she depends on her
sense of vision to be a successful prowler. But what
makes those big eyes shine like two green lanterns in
the dark with an almost supernatural light? Can a
cat really see in the dark, using only those glowing
eyes?
Well, here's the scoop on how it all works:
The feline eye structure includes the cornea, the
clear curved part of the eyeball in front of the pupil;
the iris, which gives the eye color; the lens, located
behind the iris; the retina, a network of light sensitive
cells; and the tapedum lucidum, cat terminology meaning
"bright carpet."
The cornea, lens, and retina work in much the same
way as a camera. The cornea acts like a view finder,
taking in light and transmitting it to the lens. The
lens then bends the light rays, focusing them to form
an image on the retina.
This is where the "bright carpet" comes in. This tapedum
lucidum allows the cat to take in extra light in very
dim situations. It lines most of the back of the retina
and acts like a mirror, reflecting light that was not
absorbed the first time it passed through. The result
is the glow, called eye shine, that you see when light
strikes your cat's eyes in a darkened room.
Can your cat can really see any better than you can in
a situation of total darkness? Well... It's just that
when some light is present, her light sensitive "mirror"
allows her to make better use of it. Humans can't do
that!
What does it mean when come cats' eyes glow red and
some glow green? Is it demonic influence? EEEK!
Certainly not! (I just threw that in since it is
Halloween.) The color of light reflected back from
the tapedum lucidum is related to the actual color
of the cat's eyes. Green or yellowish eyes tend to
reflect back greenish light, and blue eyes tend to
reflect back a reddish light. (Your sweet little
"red-eyed" Siamese can look pretty scary to you in
the dark!)
Of course, in addition to these wonderfully light-
adapted eyes, cats also use nonvisual signals from
their ears, noses, and whiskers. All of these factors
work together to give the cat the amazing ability to
navigate so well even in light so dim where we, the
humans, are practically helpless. Yes, cats rule
in the darkness!
Hmmmmm, here's a concept - seeing eye cats!
--THE "EYES" HAVE IT - WHAT'S BEHIND THE CAT'S GLOWING EYES?
Your cat's unusually large eyes are probably her most
striking feature, and even more so at night. Since
the cat is a nocturnal creature, she depends on her
sense of vision to be a successful prowler. But what
makes those big eyes shine like two green lanterns in
the dark with an almost supernatural light? Can a
cat really see in the dark, using only those glowing
eyes?
Well, here's the scoop on how it all works:
The feline eye structure includes the cornea, the
clear curved part of the eyeball in front of the pupil;
the iris, which gives the eye color; the lens, located
behind the iris; the retina, a network of light sensitive
cells; and the tapedum lucidum, cat terminology meaning
"bright carpet."
The cornea, lens, and retina work in much the same
way as a camera. The cornea acts like a view finder,
taking in light and transmitting it to the lens. The
lens then bends the light rays, focusing them to form
an image on the retina.
This is where the "bright carpet" comes in. This tapedum
lucidum allows the cat to take in extra light in very
dim situations. It lines most of the back of the retina
and acts like a mirror, reflecting light that was not
absorbed the first time it passed through. The result
is the glow, called eye shine, that you see when light
strikes your cat's eyes in a darkened room.
Can your cat can really see any better than you can in
a situation of total darkness? Well... It's just that
when some light is present, her light sensitive "mirror"
allows her to make better use of it. Humans can't do
that!
What does it mean when come cats' eyes glow red and
some glow green? Is it demonic influence? EEEK!
Certainly not! (I just threw that in since it is
Halloween.) The color of light reflected back from
the tapedum lucidum is related to the actual color
of the cat's eyes. Green or yellowish eyes tend to
reflect back greenish light, and blue eyes tend to
reflect back a reddish light. (Your sweet little
"red-eyed" Siamese can look pretty scary to you in
the dark!)
Of course, in addition to these wonderfully light-
adapted eyes, cats also use nonvisual signals from
their ears, noses, and whiskers. All of these factors
work together to give the cat the amazing ability to
navigate so well even in light so dim where we, the
humans, are practically helpless. Yes, cats rule
in the darkness!
Hmmmmm, here's a concept - seeing eye cats!