Why do the eyes of some animals for example cows dogs ets shine in the dark?

Cats are the most famous for their "glowing" eyes. Cats, dogs, and many nocturnal creatures appear to have glowing eyes because the back of their eyeballs include a special reflective layer that allows them to see clearer at night. The layer is called the tapetum lucidum. It increases the quantity of light caught by the retina. The tapetum lucidum collects and re-emits light back to the retina, giving the rods a second chance to absorb the image. As this light is reflected off the tapetum lucidum, the animal's eyes appear to glow.