Naked Science Forum

Life Sciences => Plant Sciences, Zoology & Evolution => Topic started by: steelrat1 on 02/12/2010 18:14:13

Title: can cats see green light?
Post by: steelrat1 on 02/12/2010 18:14:13

I was playing with my cat this eve with a Red laser pointer Output wavelength: 650 nm. and the cat would chase it all over the floor but when i used the green laser pointer 532 nm which is brighter, the cat would look past it and take no intrest in it at all, but when switched back to the red he would continue on running after it, so are cats blind to green light?

Phil

Title: can cats see green light?
Post by: Don_1 on 03/12/2010 10:40:11

Cats have evolved an eye suitable for the carnivorous hunter which they are. Humans evolved an eye suitable for the hunting and foraging omnivore which we are, or at least, used to be.

The human eye has more 'cone' receptors (which are sensitive to fine detail) than the cat, while the cat has more 'rod' receptors.

The overall effect of this, is that cats see roughly the same light as a human with colour blindness. Blue, against any other colour, is fine for them, but the red to green spectrum can be confusing. You may find that on different background colours, your cat will see the green light better than the red.

Title: can cats see green light?
Post by: Bored chemist on 03/12/2010 11:51:00

That asks nearly as many questions as it answers.
I thought that cats were colour blind. Fair enough- they don't need to tell if their prey is "ripe".
However I would expect a colour blind person to be able to see the spot from a green laser or a red one, though they might not be able to tell which was which.
In any case, whatever the colour, the laser is very bright and I would expect that to get the cat's attention.

I need to find a green laser and a cat.

Title: can cats see green light?
Post by: steelrat1 on 15/12/2010 18:42:33

so after a few weeks i still have no answer..   [:(]

Title: can cats see green light?
Post by: SteveFish on 16/12/2010 01:34:15

The only thing I can think of is that the red region is optimal for rod photoreceptors, and cats have more of these than critters adapted more to daytime vision. In any case, I think the frequency sensitivity of the cat's eye should have been well characterized by now. If you have a decent university library available you could pin this down pretty quickly, otherwise you are stuck with Google Scholar. 

Title: can cats see green light?
Post by: danielpower on 16/12/2010 14:34:58

I think dogs and cats can recognize the laser beam other they wouldn't seem so curious.
[maybe if you read the OPs question properly (and lay off the Spam) you can offer a useful answer. Post shrunk-Mod]