Scientists have discovered that birds can sleep in flight. Experts measured the activity of their brains and stated that only a small fraction of birds sleep on the ground.
Experts said that swifts, songbirds, and waders can fly without stopping for several days, weeks or months. It is generally accepted that birds rely on autopilot during sleep to transport themselves and maintain aerodynamic control during flight.
To prove this, the researchers needed to identify the changes in brain activity and behavior that distinguish the waking state from the two types of sleep found in birds: slow-wave sleep (MS) and rapid eye movement (REM) sleep. Scientists have developed a special small device to measure electroencephalographic changes in brain activity and head movement in winged flight.
The professors turned their attention to frigates, as they are seabirds that fly non-stop over the ocean for weeks in search of squid, predatory fish and cetaceans. Scientists temporarily attached a small "flight recorder" to the leader of the nesting frigates. Then, the birds, without knowing it, carried the recorder during the ten-day flight. During this time, the recorder recorded EEG activity in both cerebral hemispheres of the winged head.
The experiment showed that the birds slept in both directions - back and forth. During the day, they actively searched for food opportunities. Speaking of mammals, their sleep is accompanied by a complete loss of muscle tone, when birds can even stand on one leg.
A lot of people wonder why birds sleep so little. In fact, this is simply difficult to notice. If they spend a short time during the flight on sleep, then they are in greater concentration than ever. At the end of scientific work, it is the frigates that emphasize the importance of sleep, which can push to new perspectives in the human understanding of this phenomenon and the consequences of its loss.
Galitskaya Alla