Have you ever wondered why horses sleep standing up instead of laying down like other animals? Well, that myth is only half true. It is true that horses CAN sleep standing up, but to really sleep deeply a horse actually does need to lay down.
In the wild, horses are prey animals. Horses are able to sleep standing up because if a predator was to attack a herd of horses, the horses would lose precious escape time scrambling to their feet. A horse off it’s feet is more vulnerable to attack.
But horses do lay down on their sides to sleep for periods of time, usually at night. In horse herds, even domesticated herds, one horse almost always remains standing while the others lay down and sleep, and this position is alternated through the night.
So why do horses sleep standing up? The short answer is that horses sleep standing up so they can run away faster if attacked.