Weatherford Democrat

Community News Network

January 21, 2014

Why birds fly in a V formation

Anyone watching the autumn sky knows that migrating birds fly in a V formation, but scientists have long debated why. A new study of ibises finds that these big-winged birds carefully position their wingtips and sync their flapping, presumably to catch the preceding bird's updraft - and save energy during flight.

There are two reasons birds might fly in a V formation: It may make flight easier, or they're simply following the leader. Squadrons of planes can save fuel by flying in a V formation, and many scientists suspect that migrating birds do the same. Models that treated flapping birds like fixed-wing airplanes estimate that they save energy by drafting off each other, but currents created by airplanes are far more stable than the oscillating eddies coming off of a bird. "Air gets pretty darn wiggy behind a flapping wing," says James Usherwood, a locomotor biomechanist at the Royal Veterinary College at the University of London in Hatfield, where the research took place.

The study, published online Wednesday in Nature, took advantage of an existing project to reintroduce endangered northern bald ibises (Geronticus eremita) to Europe. Scientists used a microlight plane to show hand-raised birds their ancestral migration route from Austria to Italy. A flock of 14 juveniles carried data loggers specially built by Usherwood and his lab. The device's GPS determined each bird's flight position to within 30 cm, and an accelerometer showed the timing of the wing flaps.

Just as aerodynamic estimates would predict, the birds positioned themselves to fly just behind and to the side of the bird in front, timing their wing beats to catch the uplifting eddies. When a bird flew directly behind another, the timing of the flapping reversed so that it could minimize the effects of the downdraft coming off the back of the bird's body. "We didn't think this was possible," Usherwood says, considering that the feat requires careful flight and incredible awareness of one's neighbors. "Perhaps these big V formation birds can be thought of quite like an airplane with wings that go up and down."

The findings likely apply to other long-winged birds, such as pelicans, storks, and geese, Usherwood says. Smaller birds create more complex wakes that would make drafting too difficult. The researchers did not attempt to calculate the bird's energy savings because the necessary physiological measurements would be too invasive for an endangered species. Previous studies estimate that birds can use 20 percent to 30 percent less energy while flying in a V.

"From a behavioral perspective it's really a breakthrough," says David Lentink, a mechanical engineer at Stanford University in Palo Alto, California, who was not involved in the work. "Showing that birds care about syncing their wing beats is definitely an important insight that we didn't have before." To definitively say that the birds are drafting off each other, however, the exact location of the eddies and the areas of downdraft would need to be measured on ibises, which would require flying them in a wind tunnel - a far more intrusive process than simply carrying a data logger.

Scientists do not know how the birds find that aerodynamic sweet spot, but they suspect that the animals align themselves either by sight or by sensing air currents through their feathers. Alternatively, they may move around until they find the location with the least resistance. In future studies, the researchers will switch to more common birds, such as pigeons or geese. They plan to investigate how the animals decide who sets the course and the pace, and whether a mistake made by the leader can ripple through the rest of the flock to cause traffic jams.

"It's a pretty impressive piece of work as it is, but it does suggest that there's a lot more to learn," says Ty Hedrick, a biologist at the University of North Carolina, Chapel Hill, who studies flight aerodynamics in birds and insects. However they do it, he says, "birds are awfully good hang-glider pilots."

 

1
Text Only
Community News Network
  • Why a see-through mouse is a big deal for scientists

    A group of Caltech researchers announced in Cell Thursday their success in making an entire organism transparent. Unfortunately, this isn't any kind of "Invisible Man" scenario: The organism in question is a mouse, and the mouse in question is quite dead.

    July 31, 2014

  • Screen Shot 2014-07-31 at 2.12.55 PM.png VIDEO: Five-year-old doesn't want her brother to grow up

    Sadie, an adorable 5-year-old from Phoenix, wants her brother to stay young forever, so much so that her emotional reaction to the thought of him getting older has drawn more than 10 million views on YouTube.

    July 31, 2014 1 Photo

  • lockport-police.jpg Police department turns to Facebook for guidance on use of 'negro'

    What seems to be a data entry mistake by a small town police department in western New York has turned into a social media firestorm centered around the word "negro" and whether it's acceptable to use in modern society.

    July 31, 2014 3 Photos

  • The virtues of lying

    Two computational scientists set out recently to simulate the effects of lying in a virtual human population. Their results, published in the Proceedings of the Royal Society B, show that lying is essential for the growth of a cohesive social network.

    July 31, 2014

  • Survey results in legislation to battle sexual assault on campus

    Missouri U.S. Sen. Claire McCaskill joined a bipartisan group of senators Wednesday to announce legislation that aims to reduce the number of sexual assaults on college campuses.

    July 30, 2014

  • An alarming threat to airlines that no one's talking about

    It's been an abysmal year for the flying public. Planes have crashed in bad weather, disappeared over the Indian Ocean and tragically crossed paths with anti-aircraft missiles over Ukraine.

    July 30, 2014

  • Sharknado.jpg Sharknado 2 set to attack viewers tonight

    In the face of another "Sharknado" TV movie (the even-more-inane "Sharknado 2: The Second One," premiering Wednesday night on Syfy), there isn't much for a critic to say except to echo what the characters themselves so frequently scream when confronted by a great white shark spinning toward them in a funnel cloud:
    "LOOK OUT!!"

    July 30, 2014 1 Photo

  • linda-ronstadt.jpg Obama had crush on First Lady of Rock

    Linda Ronstadt remained composed as she walked up to claim her National Medal of Arts at a White House ceremony Monday afternoon.

    July 29, 2014 1 Photo

  • Can black women have it all?

    In a powerful new essay for the National Journal, my friend Michel Martin makes a compelling case for why we need to continue the having-it-all conversation.

    July 29, 2014

  • Facebook continues moneymaking trend

    Facebook seems to have figured out - for now at least - the holy grail for all media right now: how to make money selling mobile ads.

    July 24, 2014

Must Read
Top News
House Ads
AP Video
House Leaders Trade Blame for Inaction Malaysian PM: Stop Fighting in Ukraine Cantor Warns of Instability, Terror in Farewell Ravens' Ray Rice: 'I Made a Huge Mistake' Florida Panther Rebound Upsets Ranchers Small Plane Crash in San Diego Parking Lot Busy Franco's Not Afraid of Overexposure Fighting Blocks Access to Ukraine Crash Site Dangerous Bacteria Kills One in Florida Workers Dig for Survivors After India Landslide Texas Scientists Study Ebola Virus Smartphone Powered Paper Plane Debuts at Airshow Southern Accent Reduction Class Cancelled in TN Raw: Deadly Landslide Hits Indian Village Obama Chides House GOP for Pursuing Lawsuit New Bill Aims to Curb Sexual Assault on Campus Russia Counts Cost of New US, EU Sanctions 3Doodler Bring 3-D Printing to Your Hand Six PA Cops Indicted for Robbing Drug Dealers Britain Testing Driverless Cars on Roadways
Poll

The City of Weatherford is considering an ordinance that would ban smoking inside restaurants and enclosed areas where food is prepared, sold or consumed. Do you agree with this proposal?

Yes
No
Undecided
Don't care
     View Results