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Why do cats' eyes glow in the dead of night?

Why do cats' eyes glow in the dead of night? Chloe, age 10, Berkhamsted, Connecticut

Cats and lots of other animals, Including most dogscan do. Light reflects from their eyes.. That's why cats' eyes will normally glow in photos taken in a dimly lit room or when illuminated by flashlights or automobile headlights in the dead of night.

Species with glowing eyes have evolved to see higher in low light because they either forage or seek for predators throughout the night, or they do most of their hunting here. Morning and evening. In fact, domestic cats can only see under these conditions. 16% bright As people need.

Cats do that because their pupils — the dark-looking holes in the middle of their eyes that widen and narrow in response to lighting conditions — are special. Pupils act like windows, with larger ones letting more light into the attention. And can develop into disciples of the cat. Up to 50% larger From human pupils in dim light. They even have More numbers They have a special sort of light-sensing cell at the back of their eyes greater than we do. These cells, The rods are calledcapture low-level light.

Sketches of a human, a lynx and a puma's eyes
Humans don't have a tapetum lucidum, but cats, including lynxes and pumas, do.
The Open University, CC BY-SA

Bright carpet

In addition to large pupils and lots of wands, cats have something that folks don't: a tapetum lucidum, a Latin medical term that translates to “Bright or shiny tapestryAlso generally known as “Tapetum lucidum”.The sparkle of the eyes

It is positioned behind the attention behind the attention. Retina – a skinny layer of tissue that receives light, converts the sunshine into an electrical signal and sends that signal to the brain to interpret the image.

The cat's tapetum is made up of crystalline cells which can be mirror-like, Reflection of light Back to the retina. This gives the retina a second likelihood to soak up more light.

The feline tapetum lucidum is special due to its reflective composition. Riboflavin, a sort of B vitamin. Riboflavin has unique properties that enhance light. Specific wavelength Cats can see thoroughly, greatly increasing the retina's sensitivity to low light.

In cats, the tapetum often glows yellow-green or yellow-orange, but the colour varies in line with them irises – The coloured a part of their eye, which might be Green, yellow, blue or gold. Variation in tapetum color isn't unique to cats and might occur in Many species.

A dog with shining eyes
Most dogs' eyes will glow in dark places when a lightweight shines on them.
Tommy Greco, CC BY-SA

Other animals even have glowing eyes.

Many other animals that require night vision have tapetum lucidum. This includes hunters and prey alike, every part from wild foxes to livestock Sheep and goats.

Tapetum lucidum can be useful for fish, Dolphin and other aquatic animals, since it helps them see higher in murky, deep water.

Tapetum is present in terrestrial animals. The top half of the eye Behind the retina, because they should see what's on the bottom? But in aquatic animals The tapetum takes up most of the eye.because they should see around them in the dead of night.

like cats, Lemura small primate, and its close relative, the bush baby – called theNight monkey” – also has a super-reflective tapetum made with riboflavin.

Although many animals have shiny eyes, some small pet dogs lack this characteristic. Most animals with Blue eyes and a white or light colored coat have also lost this trait.

So don't panic in case your dog or cat's eyes don't sparkle. List of other species Without tapetum lucidum Includes pigs, birds, reptiles and most rodents and primates – including humans.

The Bush children's eyes are shining.
This bush kid can probably see higher at night than you.
Smart Shots International/Moment via Getty Images

Is there a shortage?

Unfortunately, animals with a tapetum lucidum Sacrifice some visual acuity For their ability to see in dim light.

That's because all that light bouncing across the tapetum's reflection could make it a bit blurry. So, a cat is required Seven times closer To see something as fast as an individual can see in a brightly lit place.

But don't worry, I'm sure your cat will look clean as a substitute of reading a book at night.