Have you ever wondered why your pet's eyes go eerily devilish when you take a snapshot of him using flash?
There's actually a valid reason for it: Your dog's eyes radiate a special luminescence called "eyeshine," a visible effect that human eyes lack. It's the same physiologic feature that makes a wild animal's eyes flare brightly in the dark. (Deer in headlights, anyone?)
This reaction to light in the dark is caused by an anatomic structure known as the tapetum lucidum (from the Latin for "bright tapestry"). It's a reflective pigment that lies behind the retina that contains photoreceptor cells that take in light and register images. Most mammals whose nighttime hunting duties require an amplification of light have this structure, which helps them see better in the dark.
See More on vetstreet.com
* Why Does My Dog... Smell So Bad
* Why Does My Dog... Scoot His Butt on Floor
* Why Does My Dog... Chase His Tail
* Why Does My Dog... Lean on Me
* Why Does My Dog... Stare at Me
* Why Does My Dog... Pass So Much Gas
* Why Does My Dog... Shake & Tremble
Source of Original Article: Why Do My Dog's... Eyes Glow in the Dark?