Why Do Certain Animals’ Eyes Glow In The Dark?

Some animals’s eyes shine in the dark because there is a special reflective layer at the back of their eyeballs (called tapetum lucidum) that increases the amount of light absorbed by the photoreceptors in their eyes. As a kid, I always believed that cats and dogs had some form of ‘organic’ radium in their eyes that made their eyes glow in the dark. I’m sure a lot of kids that age believe that too. However, as it turns out, there is no organic radium making the eyes of these animals shine. What is tapetum lucidum? The tapetum lucidum is the reflective layer … Continue reading Why Do Certain Animals’ Eyes Glow In The Dark?