Resumen de Wonder of slumber
Sleep is such a widespread phenomenon that it must be doing something useful. Even fruit flies and nematode worms experience periods of inactivity from which they are less easily roused, suggesting sleep is a requirement of the simplest of animals. But surveying the animal kingdom reveals no clear correlation between sleep habits and some obvious physiological need. In fact there is bewildering diversity in sleep patterns. Some bats spend 20 hours a day slumbering, while large grazing mammals tend to sleep for less than 4 hours a day. Horses, for instance, take naps on their feet for a few minutes at a time, totaling only about 3 hours daily. In some dolphins and whales, newborns and their mothers stay awake for the entire month following birth. Here, Drew examines the purpose of sleeping.
