Is My Dog Really Colour Blind?

DSC00958The simple answer is No, dogs are not colour blind and don’t just see in black and white, as once thought.  However, they don’t see colours in the same way humans do.  This Holidays 4 Dogs will take a closer look (pun intended!) into the subject of how dogs see.

In the eyes of humans and dogs there are cells called cones which catch light and respond to colours.  However, while human beings have three different types of cones, which combined together provide a full range of colour vision, dogs have only two types of cones which means their vision of colours is far less intense.

Scientists have discovered that rather than seeing rainbow colours like people do, the colours are much more subdued and lie within a narrower range, so that dogs only see yellow, (browns) blue and grey and colours they find particularly difficult to see are red and bright orange.

In short, while people see a range of rainbow colours from violet, blue/green, green, yellow, orange and red, dogs only see dark blue, light blue, grey, and light and dark yellow.

Hansome JakeThis doesn’t meant to say that a dog’s eyesight is poorer than humans though, because the photoreceptors in their eyes called rods (the same in humans) are far more sensitive to changes in light and movement than in people – dogs have far more rods in their retinas than people do.  This means that dogs are far better at seeing things in dim light and they are much more able to detect movement – ideal for night time hunting.

So, if you were to throw an orange ball onto green grass – to your dog, this will look like yellow on yellow – this is why gundog trainers will use orange dummies to make retrieves harder for the experienced dog or to test the dog on ‘blind’ retrieves.  A blue ball would stand out well on green vegetation, so for dogs new to retrieving – this would help make things easier for the dog.  Nevertheless, with his acute sense of smell and ability to detect movement, a dog’s lack of rainbow vision doesn’t really hold him back from processing his world and it is nice to know that his view isn’t as black and white as we once thought.