ARE HORSES COLOUR BLIND???

[princess]

HI,
REALLY WANTING TO KNOW IF HORSES ARE COLOUR BLIND, SOME PPL SAY THEY ARE AND OTHERS SAY NO!

WHICH IS CORRECT?

THANKS!

[eg]

Well I saw an article about a couple of years ago in one of the horse mags. It showed that horses do see colour but in a more faded way.

[Francis Burton]

Horses aren't totally colourblind. In common with other mammals, they can tell some colours apart but not others that we (along with other primates) can.

Our colour vision is relatively poor compared to many birds. They can distinguish even more colours than we can. Whether that means the colours we see are more faded compared to those that bird see, I don't know - there's no way to know for certain what anything looks like to another animal.

The reason why some animals have better colour vision than others comes down to the number of different types of cone cells in the retina of the eye. Humans with normal colour vision have 3 different types (with peak sensitivity at three different wavelengths). Animals like horses, dogs, pigs and squirrels only have 2 different types. Birds can have 4 or even 5 different types!

[fin]

Birds are really colour sensitive--they even have definate preferences. My lot are generally keen on yellow--yellow toys are played with first, while anything brown or black or dull is treated with great suspicion. This includes food, of course--some colours of processed parrot buiscuit-based food are thrown out of the cage with great indignation even though they doesn't actually taste any different to the rest (sad, yes--I tried it!). And while they seem to get used to a range of colours on individual people, if you turn up wearing something unexpected or out of character, they'll all 'comment' and have a good look, up and down, with a good bit of growling and hissing and grumbling if they feel a bit threatened.

Do horses display colour preferences?

[pip]

For years it was considered by scientists for various reasons that horses could not see colour, although the horse owners and riders disagreed about this!
However, as Francis states above, later research has found that in fact horses can see colour (which we always knew was right!!) So you might still see in some publications that horses can't see colours which might make it an old publication, or just that someone has copied this information from an old publication. Sorry if this isn't very gramatical.

[varkie]

According to Stephen Budiansky, studies in horses show that horses are dichromates - they have two types of cones in their eyes (humans have three), meaning that they do have colour vision, but it is limited, so they are probably like colour blind humans in how they see. Apparantly a study by David Pick showed that horses could consistently pick red from grey, and blue from grey, but not green from grey. This makes sense, as the cones in eyes do apparantly correspond approximately to blue, green & red - hence the two cones & limited colour!