Cyclops (the mythical creature, not the X-Men mutant) must have a tough life. They’re seen as dense and dumb, easily tricked by men pretending to be sheep. It’s not really their fault, though; if you only had one eye, you wouldn’t have a lot of depth, either. That is to say, you wouldn’t have a lot of depth perception; one of the advantages of having two eyes is that it allows you to see through crude camouflage, like the one Odysseus uses to get past the misunderstood monocular monster.

Binocular vision, in which an animal with two eyes is able to use them to create a three-dimensional image of its surroundings, has a bunch of useful properties. Generally speaking, the better binocular vision an animal has, the lower it’s field of vision; that’s because to create a good 3D image, the eyes need to be relatively close together. The reason prey animals have their eyes spaced far apart is because it increases their field of vision; the trade-off is visual acuity. Owls have a lower field of vision than pigeons, but their binocular vision makes them excellent bird of prey.

You can test the advantages of binocular vision yourself; take two pencils, or a pencil and pen – really, any two fine tips objects will do, but be careful if you pick swords or knives. Try to touch the tips of the objects together; should be easy enough. Now, do the same thing, but with your left eye closed, then again with your right eye closed; not so easy now, is it? Animals with fine motor skills and predators need a good degree of binocular vision in order to succeed; prey animals mostly just munch on grass, so co-ordination isn’t nearly as valuable.

It’s important to care for your binocular vision because we live in a world that assumes a great deal of depth perception. Far from just not being able to touch tips, a lack of binocular vision can mean difficulty gauging the distance between cars, or the distance between steps in a staircase. In short, not having binocular vision is dangerous! There are a few different conditions that can result in less-than-perfect binocular vision. One is strabismus, a condition in which your eye muscles are not properly coordinated; wandering or crossed eyes are the classic symptoms of this condition. An eye with reduced vision can also mess with binocular vision, as can some neurovisual problems.

The symptoms of binocular vision problems aren’t immediately obvious, but if you’ve noticed that you have a harder time discerning depth or speed than your friends and family, it may be a sign that your binocular vision is off. The best way of diagnosing such a problem is by visiting your optometrist. They may give you a prescription for a visual aid that will help the weaker eye; for eyeglasses Winnipeg can trust, choose Eyes in the Village.