![]() Humans don’t have a tapetum lucidum, but you can see something similar happening with flash photography when it causes ‘red-eye’. When light enters the eye of an animal with a tapetum lucidum the pupil appears to glow, an effect known as eyeshine. This gives the owl a second chance at collecting the light available and sending it to the photoreceptors, which helps them see better in the dark. This can make them look half asleep when they are actually wide awake and alert.īehind the retina in an owl’s eye is a layer of tissue called the tapetum lucidum, a retroreflector, that acts like a mirror and reflects visible light back through the retina. Owls will also partially close their eyes in daylight to block out the light. ![]() In bright light their pupils will adjust to allow less light in, unlike some other nocturnal animals that can only see in the dark. They have about 30 times more rods than cones which means that although they can’t see colour very well, they have excellent night-time vision.īecause owls have such good night vision, it has been suggested that they are unable to see during the day. In an owl’s eye, the retina has a large number of closely packed retinal rods. Retinal cones function at high light levels (photopic vision) and are responsible for colour vision and spatial acuteness, whereas retinal rods are responsible for vision at low light levels (scotopic vision), and only process in black and white. There are two types of photoreceptors in the retina – cone-shaped cells and rod-shaped cells. Cells called photoreceptors turn the light into electrical signals which travel through the optic nerve to the brain, which makes sense of the information it receives and turns it into an image. The lens and cornea work together to focus the light on the retina situated at the back of the eye. ![]() ![]() Owls’ eyes are similar to ours in that light enters the pupil through the cornea and passes through the lens. Owls’ eyes have adapted in numerous ways to allow them to see in the dark and dim light, and they also have evolved other characteristics to enhance their vision. Because much of their prey such as mice, voles, and other rodents are also active at night, owls need to be able to see in the dark so they can hunt their prey. Most owls are nocturnal or crepuscular, which means they are active at night or during the twilight periods of dusk and dawn. ![]()
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