Thread: Why do cat's eyes glow?

I'm not sure of this basic concept, why do cat's eyes glow and those of other animals don't?

Gab

I trust you can google that one Okay I know as little as you do
and I do love Cats of all sizes so I get curious too.

But Science and Nature docus has taught me that it is something
about their eyes that works as mirror that reflect the light and that way
they are very good at seeing in almost total darkness. They need very
little light to see things. Okay that is my pooor memory so let us look it up?
What search word shall we use. I try your text. I went to google.com

and entered in the search this

"why do cat's eyes glow"



Oboy! you had a good text there many many answers right away.
Here is just one of the top ten answers by google

Cats' eyes shine in the dark due to the presence of a light-reflecting surface called the tapetum lucidum.

so if you look for more details then most likely they have pictures and video clips and so on on it

That light-reflecting surface allow the same light to hit the retina twice. Therefore increasing sensitivity.

But our eyes absorb the excess light so we don't have glare.

msafwan thanks that is a much better description than I could give.
So these layers then need to be rather close to the cells that actually
detect light? Just a layer below? Specialized cells that have that function?

I find such interesting. So much more to learn.

Because many cats are evil and you can see it in their eyes.

If that's not the case, then the cat simply has a tapetum. All non-evil cats are more adapted than humans for living at night. Nocturnal animals like cats have a special layer in the back of their eye that reflects the relatively low light at night. Apparently this helps with their vision. The eyes do not make their own light, as in the sense of "glowing". The tapetum simply reflects the sparse light, thus allowing us humans to easily see this in the dark of night.

And I learned all this in 8th Grade Physical Science. For a physics class, it felt surprisingly like Biology concerning optics. We spent quite some time on different kinds of eyes and how they work with the various spectra of radiation.