This is one of those facts where you wonder why on earth somebody decided to come up with it to begin with, but here we go.
Have you ever wondered how you can sex a horse, minus the obvious differences that exist and are very visible between the two? Nope, well you can easily do so just by checking out the teeth of the horse.
Due to structural differences, and also space that is available, the male horse has 40 teeth while the female only has 36. So, count them and you will have your answer right before you. However, that does rely on the horse being quite content to allow you to count its teeth, so the actual task is, in all reality, much harder than it needs to be. The next time you want to tell the sex of a horse, just go for the easier method as it is certainly a lot less stressful on you.