Yes, horses typically sleep standing up in their natural environment, but they also need to sleep lying down to meet their sleep needs.
Horses are running animals with strong muscles and tough bone structures. They are able to maintain a standing posture while sleeping in a method called "sleeping continuously." This is because in the wild or historically, horses are animals that need to be ready to escape predators or other threats at all times, so they can run away from potential threats faster in a standing position. This habit also allows them to better protect themselves while sleeping.
However, horses don’t always lie down to sleep. They also need to lie down for deep sleep to get adequate rest. Typically, horses will choose to lie down and rest in an environment where they feel safer, such as in a stable or in a safe and protected pasture. In this case, the horse will usually sleep on its side or in a prone and rolled position.
Therefore, horses in the wild or in a very safe environment will sleep in a standing position, but will also need to lie down for deeper rest. This ability can be seen as part of the horse's self-preservation mechanism in the wild.
animal tags: horse