Question

Why does eye of a carnivore shine in night?

Answer 1

Answer:

It reflects visible light back through the retina, increasing the light available to the photoreceptors (although slightly blurring the image). The tapetum lucidum contributes to the superior night vision of some animals. Many of these animals are nocturnal, especially carnivores, while others are deep sea animals.

Dogs, cats, and deer have blood, and their eyes don't look like vampire eyes. Their eyes glow because of a layer called the tapetum lucidum just behind the retina. This layer reflects light because that's exactly what it's meant to do.