51�Թ�

The backs of a cat’s eyes have a layer called the tapetum lucidum, which reflects unabsorbed light back into the retinas, an adaptation to help the cat see in dim light, and causes eye shine, the glow that can be seen when light shines on them in the dark.

Their tapetum -- the light-enhancing membrane that gives many animals "shiny" eyes -- transitions in winter from the golden color most animals have to a vivid blue that is thought to amplify the low light of polar winter.

But the blue tapetum also lets up to 60% of ultraviolet light pass through to the eye's color sensors.

The tapetum, which some other animals, such as cats and cattle, also possess, sits behind the retina and reflects light back onto it, giving the receptors a second chance to gather more visual detail.

They even have a unique structure in their eyes called the tapetum lucidum, a mirrorlike membrane that allows them to see in six times less light than humans can.