Wednesday, March 1, 2017

"Wild Elephants Sleep Just Two Hours a Night"

In April 2014, Nadine Gravett tranquilized two female elephants and fitted them with actiwatches. These small devices—the scientific version of Fitbits—record movement, and researchers can use them to measure how well volunteers are sleeping. They’re usually worn around the wrist, but that’s not an option when your subjects’ limbs are literally elephantine. So Gravett had to implant them in the females’ most mobile appendages—their trunks.


Elephants can sleep standing up, so it’s difficult to eyeball whether they’re awake or asleep, especially if you’re tracking them through the bush at night. Brain activity sensors would give better answers, but an elephant’s anatomy makes it exceedingly risky to surgically implant such devices. So Manger and Gravett settled for the actiwatches instead. They also fitted satellite collars onto the animals to track their whereabouts later.


Of course, Gravett and Manger only studied two elephants, and both were adult matriarchs