Wild elephants can’t be bothered with sleep.
Who could blame them? They have good reasons to stay awake. African elephants need to gobble a few hundred pounds of food a day and stay vigilant of cunning predators. After fitting two elephant matriarchs—female elephants that lead their respective herds—with activity monitors, researchers tracked these elephants through the Chobe National Park, in northern Botswana, for just over a month. Their results, published Wednesday in the journal PLOS One, found that they slept around two hours a night. And on five nights, they didn’t sleep at all.