We are all familiar with those big beautiful eyes that steal our hearts and show more expression that than one word can say, but what do we actually know about the eye of a horse?
Did you know the eye of a horse is twice as big as a humans! Amazingly it is bigger than an elephants or the whale!
How well can a horse see in poor light?
The horses eyes have special 'light intensifying device' - the tapetum lucidum - this is a layer that reflects the light back onto the retina, you may have seen this before if you have ever tried to find your horse in the dark and their eyes 'light up' like a cats eyes, this reflective layer makes the horse see much better than its rider when in dim light at dawn or dusk which makes the horse a brilliant nocturnal animal.
How far can a horse see?
The horse can see approx 340'-360' around it with only two small blind spots, just in front, and immediately behind its body, this is why it is really important we do not approach even the most docile of horses from these blind spots as it may give them a fright when it feels an 'invisible hand' to pat or stroke it.
As a horses eyes are located on either side of its head it does not normally see objects in depth with binocular vision, it sees flat like we do if we shut one of our eyes but it is more sensitive to movement than we are, despite having lateral vision the horse is very capable with a narrow band of three-dimensional vision if it directs its gaze immediately forward, but due its long muzzle being in the way it can only do this when the object is about 6 feet away which does make you wonder how they see the jumps when riding at speed, it does explain why some horses tilt their head to one side very slightly on the approach of a jump.
What happens to a horses eye in bright light?
The horses pupil works in a different way from us humans when faced with a very bright light, our pupils narrow to a small circle whereas when the bright light is on the pupil of a horse it narrows and shrinks to a horizontal slit, this means that even when their pupils seem small there actual vision remains unimpaired.
Can horses see in colour?
Horses can see some colour, they have dichromatic vision which means they can see in the two-colour spectrum - mainly blue and green unlike us humans who have trichromatic vision, this is why it is quite difficult for horses to distinguish between yellows and greens, this is also why horse jumps are painted in two very different contrasting colours to make it easier for them to see. The horses eye really is an amazing organ!