When leaving the house at night, I’ve often said to Martin that we should leave the lights on in every room for the cats. Martin has often laughed at me and said, “the girls can see in the dark, so that’s really not necessary”. I thought this would be an interesting topic to research and share with you on a blog.
Without wanting to get too scientific, the difference between our vision and cats is in the retina. This is a layer of tissue at the back of the eye that contains cells called photoreceptors. These convert light rays into signals which are then sent to the brain and converted into the images we see. Photoreceptors are split into two different types – cones and rods. Cones are needed for vision during the day and colour, whereas rods are responsible for peripheral and night vision.
Cats (and dogs if we’re allowed to mention them), have more rod receptors and a lower number of cone receptions. Us humans have the opposite, which means we can’t see particularly well at night, but can pick up colours much better.
The average human has 20/20 vision. A cat’s vision can be as low as 20/100 to 20/200. In other words a cat has to be at 20 feet to see what we can see at 100 or 200 feet. Cats would certainly benefit from glasses, so perhaps there’s a new business for us. Cats are short-sighted which means they can’t see objects in the distance particularly well. Being able to see objects close up, certainly is a benefit when it comes to hunting (as long as the mouse is right under their nose).
Although at night cats can’t see fine detail or rich colour, they have superior night vision. Cats can see in around one sixth of the light that humans need. Behind the retina cats have the tapetum which is meant to improve night vision – this is why cats’ eyes glow in the dark.
So all in all, cats can see in the dark much better than us. But as Martin said, “how do the scientists really know”. So I’ll still be leaving the lights on for our beloved Posh and Becks. Don’t forget when you’re going away, we are happy to turn the lights on and off, as well as shut curtains – all good security. So if you need our help with cat sitting in Bedfordshire and Buckinghamshire, then just get in touch.
Perhaps there’s a topic you’d like me to write about. Just let us know.