Have you ever thought of sleeping on your legs? Do you think that we human beings can stand on legs and manage to sleep without falling down? The answer is an obvious ‘No’ but surprisingly horses manage to do so. It not only manages to relax while standing, it sleeps easily while in a standing position without falling down.
It happens so because nature has bestowed horses with a heavy body which cannot get upon when attacked easily from the ground and hence sleeping in an upright position comes handy. If attacked by predators, the horse can easily manage to run while sleeping in a standing position. Their speed is their only defense, when attacked by somebody in wild and if they lie down on ground then it could be difficult to gather themselves with their huge bodies first and then run.
Horses have such bones and ligaments in the lower part of the legs which lock together in a special way and enable horses to sleep without falling down. Their specialty to stand in this special way is called “stay apparatus.”
Horses do take a nap while lying on the floor. It is said that 45 minutes a day are suffice for a horse to lie on the ground and sleep. But more than that can cause damage to the tissues of their legs as they are quite heavy in weight. When horses feel extremely secure and safe then only they lie on floor to take their REM (Rapid Eye Movement) sleep.
When you find a horse standing with its head and bottom lips drooping, it is actually sleeping.