Sleep Habits of the Animal Kingdom
As we all know, humans prefer to sleep at night, usually for about eight hours. But not all species in the animal kingdom have the same sleep habits. Have you ever wondered if giraffes and elephants also sleep lying down like people? Or if dolphins close both eyes when they sleep like we do?
Giraffes, elephants and horses sleep standing up.

Getty Images / Moment / Lucas Ninno
While humans prefer to sleep lying in bed, elephants, giraffes and horses sleep standing up. Since it takes a bit of work for these animals to get up, which makes them vulnerable to attacks by predators, it’s safer to sleep standing. To achieve this feat, they have a special system of tendons and ligaments that allows them to lock the major joints in their legs.