Sleeping Habits of the Giraffe
- Paradoxical or REM sleep is common among giraffes as well as many other mammals during their regular sleep cycles. This REM sleep is associated with a change in EEG activity, which sometimes results in twitching of the extremities, eye movements and temporary paralysis from muscular atony, for short periods of time. Because of this and the difficulty associated with changing position from lying down to standing, giraffes are very vulnerable to their predators while sleeping.
- Giraffes appear awkward but they are actually very graceful animals in complete control of their bodies. They usually sleep while standing but occasionally lie down to sleep. When giraffes are resting while standing upright, they lay their heads against a hind leg, forming an arch. Older giraffes more often sleep standing up because it is difficult for them to rise after lying down. While lying down, giraffes will fold their legs and rest their head along their rump. Sometimes they will lay their head in the notch of an available tree.
- The giraffe is very large and the tallest of all the animals. Surprisingly, it is also one of the few that requires little sleep. The average giraffe sleeps only about two hours a day. This sleep is usually in the form of naps of only a few minutes and periods of deeper sleep averaging five minutes. When taking short naps, it will often keep one eye open and constantly move its large, eight-inch ears to stay alert for predators.
- Giraffes are even more at risk when lying down because standing back up is a difficult and lengthy procedure. They must swing their neck back and forth to attain a kneeling position, swing their neck vigorously forward to get on their hind legs and then remove the weight from their front legs to hoist themselves back up. Giraffes use safety strategies to lessen the likelihood of being attacked by an enemy while sleeping. A herd of giraffes will sleep in a star-shape pattern, with each sleeping animal facing a different direction. One giraffe will stand guard while the others are sleeping, and the rest will sustain deep sleep only for very short intervals.