The phenomenon of 'eye-shine' is seen in a variety of animal species, and is generally thought to be related to the presence of an intraocular reflecting structure, the tapetum lucidum. The tapetum lucidum is a biologic reflector system that is a common feature in the eyes of vertebrates. It normally functions to provide the light-sensitive retinal cells with a second opportunity for photon-photoreceptor stimulation, thereby enhancing visual sensitivity at low light levels.
When light enters the eye, it's supposed to hit a photoreceptor that transmits the information to the brain. But sometimes the light doesn't hit the photoreceptor, so the tapetum lucidum acts as a mirror to bounce it back for a second chance.
A large number of animals have the tapetum lucidum, including deer, dogs, cats, cattle, horses and ferrets. Humans don't, and neither do some other primates. Squirrels, kangaroos and pigs don't have the tapeta, either.
References:http://sciencing.com/animals-tapetum-lucidum-8541210.html
http://www.npr.org/templates/story/story.php?storyId=96414364
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