Three Alpine swifts have set world record in completing a non-stop 200-day journey across the Sahara desert, a 1,240-mile journey, while going through sleep during flight, scientists said.

Ornithologists have asserted for decades that Alpine swift can stay airborne for an extreme duration of time. The data published in Nature's Communication is the first evidence confirming this assertion. Ornithologists and Swiss Ornithological Institute and Bern University of Applied Sciences, Engineering and Information Technology tracked the birds using lightweight sensors that sensed their wing movements and body angles.

To date, such long-lasting locomotive activities had been reportedly only for animals living in the sea, such as marine mammals dolphins and whales that perform "unihemisphere sleep" with half their brains alert and active.

Alpine swift, on the other hand, may be aerodynamically optimized, but flying still requires a considerable amount of energy for continuous control. Thus, it is surprising to learn that extreme-fliers can remain airborne for migration, "foraging and roosting" over an extended period of time.