Birds Avoid Mid-Air Collisions By Following These Two Simple Rules
While studying new technologies for drones, researchers discovered the instincts that keep birds from colliding.
Theexperience is familiar to everyone.You're walking down acrowded sidewalk,see that you're about to walk into another personhead-on, and then you bothengage in agraceless left-right-left samba. It's anawkward encounter that seemsavoidable, andif people were more like birds, it would be. That's according tothatdescribestwo simple but crucial adaptations that allow birds to fly in dense flocks without colliding.
The scientistsresponsible for the study arefrom Australia’s University of Queensland,and as part of the team'sresearch, they'vebeenlooking to the natural worldfor ways todevelopdrones that canavoid mid-air collisions as the skiesget more crowded. Birds, theythought, might provide some good lessons.
"Given that head-on collisions have rarely been observed or reported in birds, we decided to ask whether birds use strategies to avoid them," saidMandyam V.Srinivasan, the head of the research group,in an email.
To uncover the birds'internal programming, the researchersconstructed a 70-foot-long tunnel outfitted with bright lights so that the test subjects—male Budgerigars or “budgies”—could easily see each other. Usinghigh-speed video cameras to capture every movement, they then released a bird at each end of the tunnel and recorded their near-misses as the budgies barreled towards each other.
Over the course of four days, seven budgie pairs made 102 flights with no mishaps. And when the researchers reviewed the video, they saw that the birds avoided anyaerial mishapsthanks to two evolutionary traits. About 85 percent of the time, the birds turned right upon approach."This seems to be a simple, efficient and effective strategy for avoiding head-on collisions,"Srinivasan said.
The budgiesalso seemed to decide whether to fly over or under an approaching bird, and the pairs rarely made the same choice—a secondary level of compexity humans don't have to worry about on the sidewalk. How the bird'smake thesedecisions is an open question; the researchers speculate that either each budgie prefers one flying height over the other, or flock hierarchy determines who flies high and who flies low.
For Srinivasan and his team, the resultsweren't a completesurprise."It is known, for example, that aircraft pilots are taught to veer to the right when they perceive an imminent head-on collision with another aircraft," he said. "But it was interesting to discover that biology has invented this rule millions of years ago."
Why humans haven't adapted a similar strategy isn't clear. Srinivasan says that it could be because we haven't lived in high-density living situationslong enough to develop suchinstincts, or possibly because head-on collisionsat walking speeds are rarely fatal—and thus not ahigh priority evolutionarily speaking.
Either way,there'sno question getting caught in one of these tangles can leaveyou feeling silly, so maybe this is a trick humansshould borrow from birds.Thenext time you're on the sidewalk and find yourself in such a situation,go right. Hopefully others will catch onand a movement will begin.
Either way,there'sno question getting caught in one of these tangles can leaveyou feeling silly, so maybe this is a trick humansshould borrow from birds.Thenext time you're on the sidewalk and find yourself in such a situation,go right. Hopefully others will catch onand a movement will begin.