Why do #cats run into glass doors? Do they think glass is invisible?

• 1 April 2015
• By Brian Edwards

Every cat owner who also owns a glass door will be aware of this phenomenon

Cats may be aloof and you may love or hate them for it

But it's virtually impossible not to giggle when they run into some glass thinking it's not there (and then immediately feel sorry for them of course, we're not monsters).

Like this for example (although the fact that it was still included in the French broadcast is the funniest thing about the clip).



So why does it happen? Aren't cats supposed to have amazing eyesight? They are, aren't they? Are they impervious to glass? Does it seem like a force field to them or something? Do they think glass is like some magic stuff from Star Trek?

Well, in actual fact cats DON'T have as good eyesight as us puny humans in many ways

Things cats beat most of us paws down at, in the eyesight stakes: peripheral vision, seeing at night and distinguishing movement.

The visual field of a cat is 200 degrees as opposed to our 180 degree vision, which means they can see more at the sides.

Things we do better at: colour and well, seeing stuff in focus.

And that's the clincher

According to scientists, humans have a lot of colour and detail receptors in our eyes, which are cone shaped, but cats have more rod shaped cells which are far better are discerning stuff in dimmer light and at night. And because those types of cells update information a lot quicker, it means cats are much better at noticing things moving at speed.

But on the flip side it means they don't see colour or make out details so well. Stuff that is further than about 20 feet away is pretty blurry if you're a cat.

This is roughly what Boris Johnson announcing the Tory election campaign earlier today looked like to us (top) and cats (below).

Getty

Lucky old cats don't see so much

And this, we think, explains why cats have trouble with glass doors. If they are heading towards them at speed they possibly only notice a moment too late. The lack of colour and detail definition, as described in the image above (they do better with blues) will play a factor - as will the fact light is not being reflected off it.

Although, we have walked into very clean glass doors before. And maybe it's just that.

SOURCE