We are often asked the question why an Elephants eye does not give you the same bright shiny feedback as most other mammals at night when you shine a spotlight – so here is your answer ?
An elephant’s eye, like the eyes of many other animals, doesn’t have the same reflective layer behind the retina known as the tapetum lucidum that’s found in animals like cats and dogs. The tapetum lucidum is responsible for reflecting light back through the retina, which enhances night vision and gives animals’ eyes that characteristic “eye shine” when light is shone upon them in the dark.
When light enters the eye of an animal with a tapetum lucidum, it passes through the retina where the photoreceptor cells (rods and cones) capture the light signals. Any light that isn’t immediately captured by the photoreceptors can pass through the retina and hit the tapetum lucidum, which then reflects the light back through the retina, giving a second chance for the photoreceptor cells to detect it.
In animals without a tapetum lucidum, like elephants, the light that enters the eye is either absorbed by the retina’s photoreceptor cells or transmitted through the eye, without any additional reflection. As a result, when a spotlight is shone on an elephant’s eye at night, you won’t see the same kind of bright reflection (eye shine) that you might observe in animals with a tapetum lucidum.
It’s also worth noting that the ability to see eye shine depends on various factors, including the angle of the light, the animal’s eye anatomy, and the presence of the tapetum lucidum. Different animals have evolved different adaptations for night vision based on their ecological needs and behaviors.