Why are my cats different?
January 28, 2006 10:34 AM Subscribe
Why does cat A have evil red eyes when I photograph her and cat B have evil green eyes when I photograph her?
My guess:
The red light is reflection of the eye's lens. You see this in photos of humans too.
The green (or yellowish) light is reflection off the tapetum, a reflective area behind the retina. Many vertebrates (but not humans) have tapeta.
Why lens reflection from one cat and tapetum reflection from another? Probably the cats have slightly differently shaped eyes. (I suspect that after 9500 years of domestication, even with feral crossings, cats are less selected for good eyesight, allowing eye shape to drift with time.)
posted by orthogonality at 10:49 AM on January 28, 2006
The red light is reflection of the eye's lens. You see this in photos of humans too.
The green (or yellowish) light is reflection off the tapetum, a reflective area behind the retina. Many vertebrates (but not humans) have tapeta.
Why lens reflection from one cat and tapetum reflection from another? Probably the cats have slightly differently shaped eyes. (I suspect that after 9500 years of domestication, even with feral crossings, cats are less selected for good eyesight, allowing eye shape to drift with time.)
posted by orthogonality at 10:49 AM on January 28, 2006
I could be because your cats are two different breeds. Most cats breeds have a refelective layer behind the retina called a tapetum that helps their night vision acuity. This tapetal colour gives 'green eye' or 'blue eye' effects when photographed. But, some cats breeds (like certain siamese) have no tapetal pigment and show the 'red eye' effect like in humans. Just a note, but if you see a 'green eye' effect in humans, it could be a warning of a serious condition.
(On preview, what orthogonality said...)
posted by Isosceles at 10:52 AM on January 28, 2006
(On preview, what orthogonality said...)
posted by Isosceles at 10:52 AM on January 28, 2006
Blue-eyed cats often lack the tapetum lucidum. That will cause a different reflection. Sometimes cats that have the tapetum will have different reflections based on photography conditions.
We have two cats, a blue-eye and a green-eye. The blue gets red-eye, the green gets green-eye.
posted by Dipsomaniac at 11:03 AM on January 28, 2006
We have two cats, a blue-eye and a green-eye. The blue gets red-eye, the green gets green-eye.
posted by Dipsomaniac at 11:03 AM on January 28, 2006
Response by poster: You all seem to be correct: cat A has blue eyes and cat B has gold eyes. I have learned a new thing. Thanks.
posted by DeepFriedTwinkies at 11:11 AM on January 28, 2006
posted by DeepFriedTwinkies at 11:11 AM on January 28, 2006
Our sister and brother have green and gold reflecting tapetum, respectively.
If it's orange, your cat is a replicant. (If I could afford a real cat, would I be working in a place like this?)
posted by Aknaton at 12:58 PM on January 28, 2006
If it's orange, your cat is a replicant. (If I could afford a real cat, would I be working in a place like this?)
posted by Aknaton at 12:58 PM on January 28, 2006
Gee. Thanks to this thread, I have learned that there is actually a site called Rate My Kitten.
Sure beats the heck out of MySpace...
posted by mykescipark at 1:31 PM on January 28, 2006
Sure beats the heck out of MySpace...
posted by mykescipark at 1:31 PM on January 28, 2006
The red light is reflection of the eye's lens.
No, it's a reflection from the retina. Lenses are, of course, transparent.
posted by kindall at 1:42 PM on January 28, 2006
No, it's a reflection from the retina. Lenses are, of course, transparent.
posted by kindall at 1:42 PM on January 28, 2006
This thread is closed to new comments.
posted by easternblot at 10:49 AM on January 28, 2006