If you've ever taken a photo of a cat, you've probably noticed that cats' eyes react pretty dramatically to the flash of a camera. Most of the time, a cat in a photo will have really dramatically glowing green eyes. Other cats have reddish or pink glowing eyes. The result is always pretty funny. It's led to a whole series of LOLcats images about "mah lazers" because those glowing orbs look for the world like dangerous scifi weapons!

There's actually a reason that some cats' eyes glow green and others glow blue, and you can see it illustrated pretty clearly in this photo of a white kitty with heterochromic (two-toned) eyes.

Most animals, except those with albinism, produce a pigment called melanin. It's what makes dark skin dark, brown eyes brown, and black hair black. Most creatures have lots of melanin in the part of the pupil called the retinal pigment epilthelium. Melanin absorbs a lot of the light from a camera's flash, so only a mid-wavelength color like green or blue shows up from a camera's flash on the eye. So kitties with brown, gold, or green, or amber eyes usually have bright-green, glowing eyes in flash camera photos.

On the other hand, cats who have little to no melanin to absorb the light from a camera's flash automatically show up as the color of the longest wavelength: red. This happens to cats who have blue eyes or to the rare kitties with true albinism (which causes pink eyes). So you can bet that photos of your brown-eyed cat will show green "lasers" and that pics of your blue-eyed cat will show two glowing red orbs! Pretty cool, huh?

What picture are your kitties' eyes in flash photos?