What is a horses sleep wake cycle?

Horses have a unique sleep-wake cycle that consists of both deep sleep and lighter rest periods. They typically sleep for about 4-5 hours in a 24-hour period, with most of their sleep occurring in short intervals throughout the day and night. Horses are able to sleep while standing, thanks to a locking mechanism in their legs, but they require periods of REM sleep, which occurs when they lie down. Their natural instincts also dictate that they remain alert to potential predators, leading to a fragmented sleep pattern.