One of the first things most people notice about a horse is the colour of their coat. Rumours abound that different coat types and colours influence horse behavior such as chestnuts being sensitive and hot-blooded. Horse lovers are willing to study just about anything horse and scientists can love horses just like the rest of us. So, does coat colour affect horse behaviour? As with all complicated things, the answer is both yes and no.
The various coat colours of horses are controlled by eleven different genes. Two of those genes control the basic four coat colours. Other genes change those colours through diluting them, overriding their effects or creating patterns of pigmented and non-pigmented colours. The relevant bit here is that those same genes that determine coat colour also play roles in other processes that can affect horse behavior and health.
Bay (base color) v Chesnut horse
Research is limited when it comes to the connection between horse behavior and their coat colour. One study shows that chestnut horses are bolder and more likely to approach the unfamiliar than bays but no more likely to be difficult to train. Brave chestnut horses may seem hot-blooded because they’re more liable to investigate the unknown. There may also be some anthropomorphization from our view that human redheads are fiery and hot-tempered. Still, in that study, breed, gender and age were better at predicting a horse’s behaviour and personality than colour.
The Ice cool Grey horse
However, on the flip side of the coin, a study of Icelandic horses found some evidence that silver coloured horses are more nervous and difficult to control. Silver coloured horses tended to more cautious in new situations but no more reactive than any other horse. One explanation is that the gene for a silver coat can also cause eye and hearing problems, so the cautious nature may be sensory issues playing out.
Horse behavior and color – Is it linked?
What it all boils down to is not to judge a horse by its colour. While some coat colours may be linked to behaviour, the evidence is pretty weak. Chances are you remember hot-blooded chestnuts as proof of the stereotype and are forgetting the calmer ones. The human brain likes to partake in confirmation bias whenever it can.