Scientists half-track 2 elephants in African nation to seek out out additional concerning the animals' natural sleep patterns.
Elephants in zoos sleep for four to 6 hours on a daily basis, however in their natural surroundings the elephants unweary for less than 2 hours, chiefly in the dark.
The elephants, each matriarchs of the herd, generally stayed awake for many days.
During this point, they cosmopolitan long distances, maybe to flee lions or poachers.
They solely went into speedy eye movement (REM, or dreaming sleep, a minimum of in humans) each 3 or four days, once they slept lying down instead of on their feet.
Prof Paul trough of the University of the Rand, South Africa, aforementioned this makes elephant sleep distinctive.
"Elephants ar the shortest sleeping craniate - that appears to be associated with their massive body size," he told BBC News.
"It looks like elephants solely dream each 3 to four days. Given the well-known memory of the elephant this calls into question theories associating slumber with memory consolidation."
To find out additional concerning their sleeping habits within the wild, faculty member trough and his analysis team fitted the scientific equivalent of a fitness huntsman beneath the skin of the animals' trunks.
The device was wont to record once the elephants were sleeping, supported their trunk staying still for 5 minutes or additional.
The two elephants were conjointly fitted with a gyro to assess their sleeping position.
Both elephants were followed for 5 weeks, giving new insights into their natural sleep patterns.
"We had the thought that elephants ought to be the shortest sleeping craniate as a result of they are the most important," aforementioned faculty member trough.
"Why this happens, we're not extremely certain. Sleep is one among those particular mysteries of biology, that together with intake and replica, it's one among the biological imperatives. we have a tendency to should sleep to survive."
