SoylentNews

takyon [soylentnews.org] writes:

Researchers have used "scientific fitness trackers" to track the sleeping habits of elephants [bbc.com]. It turns out that they don't sleep very much at all:

Wild African elephants sleep for the shortest time of any mammal, according to a study. Scientists tracked two elephants in Botswana to find out more about the animals' natural sleep patterns. Elephants in zoos sleep for four to six hours a day, but in their natural surroundings the elephants rested for only two hours, mainly at night.

The elephants, both matriarchs of the herd, sometimes stayed awake for several days. During this time, they travelled long distances, perhaps to escape lions or poachers. They only went into rapid eye movement (REM, or dreaming sleep, at least in humans) every three or four days, when they slept lying down rather than on their feet.

Prof Paul Manger of the University of the Witwatersrand, South Africa, said this makes elephant sleep unique. "Elephants are the shortest sleeping mammal - that seems to be related to their large body size," he told BBC News. "It seems like elephants only dream every three to four days. Given the well-known memory of the elephant this calls into question theories associating REM sleep with memory consolidation."

Also at Wits University [wits.ac.za] and Reuters [reuters.com].

Inactivity/sleep in two wild free-roaming African elephant matriarchs – Does large body size make elephants the shortest mammalian sleepers? [plos.org] (open, DOI: 10.1371/journal.pone.0171903) (DX [doi.org])

Original Submission