The eyes of animals shine at night when light falls on them. Why???

Hi meissatish,Many animals have a mirror-like layer at the back of their eyes (tapetum of the retina which helps them see better in the dark) that reflects background light like tiny searchlights. Humans don't have this tapetum lucidum layer, so red-eye photos are something different. The red color is a reflection of the many blood vessels that nourish our eyes, like the pink color of our lips. We only notice this in flash photos because the camera flash is bright for such a short time, 1/1000th of a second or less, so our pupils don't have time to close down or constrict. Humans and apes do NOT see in the dark due to a lack of the tapetum (reflective retina),Human eyes only shine red when a flash from a camera hits them at the right angle. This is due to blood vessels in the eye and the flash hitting before the pupils have time to constrict.