African elephants are the largest land animal, and evidence suggests that larger mammals tend to sleep less. But many studies on elephant sleep have either been done in a captive setting or were unable to accurately distinguish rest from sleep. To study in more detail how elephants sleep in the wild, researchers monitored two free-roaming African elephant matriarchs in Chobe National Park, Botswana, for 35 days.

GETTY African elephants doze for an average of just two hours a day in the wild

The researchers fitted the elephants with an implant in the trunk activated to monitor sleep accurately, and a collar with a gyroscope to track sleeping position.

Current study shows that in their natural habitat, wild, free-ranging elephants sleep only for two hours per day Professor Paul Manger - Study leader

They found that the elephants slept an average of two hours a day, which is the shortest known sleep time of any land mammal. On several days during the study, the elephants went without sleep for up to 46 hours and travelled long distances of around 30 kms (18.6 miles) during these periods, possibly due to disturbances such as lions or poachers. And the elephants slept lying down only every few nights.

GETTY Evidence suggests that larger mammals tend to sleep less

GETTY Elephants sleep time of two hours a day, is the shortest known sleep time of any land mammal

The researchers said this could limit their potential for daily rapid eye movement (REM) sleep, raising questions about when elephants experience that sleep state. While only two elephants were tracked, the researchers say their findings provide new insights into the sleep patterns of elephants in the wild. Study leader Professor Paul Manger, of University of the Witwatersrand in South Africa, said: “Studies of sleep in captive elephants have shown that they sleep for four to six hours per day.“

GETTY Some elephants went without sleep for up to 46 hours

10 amazing facts about elephants Wed, April 12, 2017 Fun facts about elephants for world elephant day. Play slideshow Getty Images 1 of 10 African elephants are the largest land mammals on the planet