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Why Birds Fly In a V Formation
sciencehabit writes "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 — where researchers took to microlight planes and recorded birds strapped with GPS in-flight — 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."
I remember being taught this as a child in the 80s.
I'm assuming then that the other birds are freeloaders.
This has long been the explanation of why birds fly in an echelon formation and why throughout a migration the front ranks cycle from the front to the rear. As the leading rank of birds tire, the next rank takes over allowing them a bit of a rest.
Two of my imaginary friends reproduced once
In the northern hemisphere they actually fly in an A formation. Only in the southern hemisphere do they fly in a V.
Something to do with the Coriolis effect.
Learned it in Elementary School, maybe we had the same teachers at one point?
People once told me 68K ram was all we needed,
about getting funding for *my* study on why dogs lick their balls.
I went quickly over TFA and I can't find a mention of leader birds switching turns to avoid exhaustion. Not much value in their research.
Everything I write is lies, read between the lines.
Of pretty much anyone I know, they'd all reply with this answer. I've never heard another explanation, actually. Was this study done by interns trying to practice a study procedure as opposed to figure out something important/unknown? Not the type of paper I'd expect any scientist to fight to get their name on.
Obviously the birds fly in a V formation to avoid being pooped on by the leader birds.
Yes I had heard this explanation in the late 40's. But I guess all that old research is in a Canadian dump now and has to be done over again.
If you're checking whether they orient their balls towards the sun before they lick, then yes, you're sure to get funding.
Spent All My Mod Points
What a waste of money.
No, it was assumed. In science, there is a massive gap between assumption and knowledge. The point of science is to bridge that gap.
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
Although this may not be the first time the airflow effects have been measured "in the wild", I cannot remember any previous instance.
There are a lot of things "everybody knows" that have never been verified. It doesn't hurt to run the experiments and perform the verification.
"Everybody knew" that time passed slower on a body moving faster; after all, Einstain had said so. Still, it wasn't until we put sufficiently accurate chronometers on spacecraft that we really knew it, because they did, in fact, show that the spacecraft experienced less time than the ground stations. Although surface installations are "orbiting" at about 1000 MPH (too easy with a 24 hour day and 24000 mile circumference), and are at the 1G level of the Earth's gravity well (also has an effect), the space craft are moving at about 16000 MPH (90 minute orbit at 100 mile AGL) and still at nearly the 1G level of the gravity well. That 15000 MPH difference shows up readily, even after the adjustment for gravity.
They don't want to get shit on by the bird(s) in front!?
Damn it slashdot, read the article. Although it doesn't claim explicitly that this is the first time this hypothesis has been tested, if anything, it appears this was just a study that verified that this hypothesis is correct. People already posited this and apply it for jets (see jets that fly in echelon formation), but, at least what is said and implied in TFA, this seems to still be something that is a matter of debate.
The real breakthrough was determining why one side of the formation is often longer than the other. They determined it was because there were more birds on one side. (Really? Who didn't know this?)
Schrödinger's cat is not amused—maybe.
The point of the article is that the wake left by a flapping wing is more complicated than the wake left by a fixed wing such as an aircraft. It turns out (and I don't remember reading about this before) that the birds are actually adjusting their position and flapping to get the most benefit.
This makes sense logically, but this is the only study I know of that actually verified it. You know, like science requires...
Didn't Mythbusters experimentally show that the V formation saves fuel?
But that plan kind of pooped out.
Probably less a waste of money than your science education was apparently.
Would that be Elbert Einstain you speak of?
I just wonder if birds cyclke through the lead position, like organized bicyclists do.
It was assumed by many, but it's been tested in one manner or another for decades.
a definitive account of the aerodynamic implications of these formations has remained elusive.
I guess it depends what you consider "definitive" -- and that's going to be different for each type of bird. The aerodynamic implications have been tested before, and the conclusions, unsurprisingly, were the same.
But what is the advantage to flying in formation rather than in the disorganized flock that most short-range birds seem to prefer? These aren't bureaucratic minds pursuing order for the sake of order - instinctual behaviors almost always exist because they bestow a definite advantage upon those who display them. Or at least they did at some point in the past, and don't carry enough of a cost to have been bred away since the historical conditions changed
--- Most topics have many sides worth arguing, allow me to take one opposite you.
No, no - it's you can save yourself either 15%, OR "moron car insurance". And really, who doesn't want to save themselves from moron car insurance? Though that 15% sounds pretty tempting too...
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Indeed they do. But they took 100mil more years to figure it out.
Maybe, although it also makes sense explaining it from the individual agent perspective. If I'm driving over a long segmented bridge, then every time I hit a new segment, it causes my car to bounce slightly. If I'm driving at the 'wrong' speed the end of my bounce coincides with the next segment dip, meaning my bounces get increasingly worse. So I slow down a bit to avoid this effect. If I'm a bird, and I'm flying behind and to the left of another bird, and every time my own wings aren't providing lift happens to coincide with a down draft that's coming at regular intervals, I'll instinctively adjust the timing of my wing beats so my own flight is as stable as possible.
If you actually examine it and it's creation process a beaver dam or termite mound is actually a pretty impressive feat of engineering possessing many functional details at least as impressive as anything found in most human dwellings. Passive environmental regulation systems. Near-optimal structural layout based on environmental factors. And in the case of ants at least this is accomplished with near-zero cognitive problem solving abilities.
There's no shame in recognizing the brilliance of emergent systems, our own brilliant self-reflective minds and all we've created are themselves a manifestation of the self-arranging pattern. Also vortex surfing is a far more complicated and dynamic process than drafting. When drafting you simply travel within the slipstream of another, reducing your airspeed to roughly zero regardless of groundspeed, virtually eliminating aerodynamic drag. In vortex surfing you are instead leveraging the eddy currents created by the wings in front of you, amplifying the lift generated by your own. In a way Dragonflies do an even more sophisticated version of this in solo mode - in forward flight their front wings generate almost no thrust, instead generating a stream of powerful vortex "bubbles", which their rear wings can then leverage to generate considerably more thrust than having both wings in "thrust mode" could possibly manage.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Or they just like your nice warm body heat against their back feet.
While I certainly won't deny a certain... aristocratic quality to cat behavior, I think it's also important to recognize that along with many similarities their are certain aspects of feline nature which are fundamentally alien to us, and that ascribing human motives to their behaviors is thus pretty much guaranteed to be wildly inaccurate on a regular basis. Come to think of it there are certain similarities to intersex communication - men and women share many similarities, but also many differences, and if we try to interpret each others behaviors in terms of our internal model of "person" as "someone like me" we will inevitably have some major tragic and/or hilarious misunderstandings. And really that extends to just about everyone to some degree, When I try to interpret your actions, the most natural thing for me to do is to assume you are motivated by whatever would motivate me to act like you are acting, but that ignores the potentially substantial differences between individual values, interests, and priorities, not to mention actual difference in individual cognition, of which things like autism or extroversion are only particular extremes in a very multidimensional landscape.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
That dragonfly tidbit was very interesting, thank you..
He tried to kill me with a forklift!
I remember having watched a special episode of Mythbusters a few days ago where they also made experiments with small airplanes in different flying formations. They tried the classic birds' V formation, an extended version of that or straight line formations. It was actually impressive how strongly fuel consumption and manoeuvrability were affected by some seemingly small variations of the formations.
Here is a small clip:
http://dsc.discovery.com/tv-shows/mythbusters/videos/extended-v-minimyth.htm
Axes high!
Some ant species have been found to engineer underground agriculture systems where they create rooms and tunnels that foster the flow of moist air through them, so they can grow fungi to eat.
Wiki Ant-Fungus Mutualism. It's pretty fascinating.
What's next, Dr. Romero investigating the moisturizing properties of dihydrogen monoxide?
I want to delete my account but Slashdot doesn't allow it.
Think like an ibis, goose, or ... hey ... a human pilot.
You want to fly with your buddies. Do you form: ... like cars in traffic. ... an excellent formation for creatures or aircraft flying together and trying to avoid collisions ... .... distances get adjusted to maximize flight efficiency.
- everyone in line a single long line one behind the other? No because then all you can do is see is the person ahead of you and you are constantly surprised by their sudden accelerations (+ or -'ve) and you'd find yourself flying way slow and then way fast to catch up
- everyone line abreast i.e. beside each other stretching out to either side? No because then you have to keep looking from one side to the other trying to keep your distance from the next person and the same speed as them who are trying to keep speed with you so everyone ends up kind of rushing ahead then slowing down especially 'cause you can't see the partner two individuals away.
OR
- a vee formation where everyone gets behind and a little to the left or right of someone else? Yes. A leader will emerge if not already defined by the flock/squadron as top alpha creature/plane end everyone can easily see the individual in front to adjust to their speed and position, everyone can see approaching obstacles (in which case they can anticipate the movement of the individual they're following), and everyone can relatively easily take a quick look at the individuals all around them
AND _THEN_
See how that works? Formation shape for safety from collision and then distances adjusted for flight efficiency. ... and it's why birds do it. Oh, and wolves, small herds, orcas, etc. Kind of anything travelling close with purpose .. even schools of fish are composed of a fractal pattern of 'v' formations ie. if not in front of everyone, the individual fish will get behind of, and to the side of the fish ahead of them ... if they didn't we would see fish CUBES instead of fish BALLS
It's why aircraft fly in such formations
Honestly, formations based on aerodynamics?! It's a flock of ibises, Jim, not rocket scientists!
"Consensus" in science is _always_ a political construct.
That's the real reason they fly this way.
Remember this as they fly overhead and prepare to drop a payload on you - which always seems to be coordinated and inescapable to those in their path.
This illustrates the state of modern science. There is/was no debate: it is clear that evolution will reward mechanical efficiency, like it always does. Pelaton cyclists take turns at the front and draft each other, and you need only compare a road-race to a time-trial to see the efficiency gain (look at the length of the race, and how few small breakaways succeed). Bird's V-formations allow the same efficiency gain, and an evolution process too stupid to learn this and take advantage would have died out long ago. The only debate should be whether there are any other additional pressures towards this (such as females preferring the flying aesthetics in funny ways, leading to strange sexual selection patterns, but it should be clear that there are unlikely to be any of these). Is there any biological organism that doesn't seek out ease over difficulty? How some could think that birds wouldn't is beyond me.
There are also phenomena like the phase-locked loop that illustrate how feedback can contribute to stability in a dynamical system. That birds have brains, and brains relate sensory input to motor output, and involve lots of internal feedback should surely suggest that such a mechanism is at work.
How good is the mathematics and physics intuition of these people? It's amazing how things that are obvious to those that know a little maths are somehow strange wonders that are heralded as scientific discoveries to those who don't.
John_Chalisque
Jet engines are natures way of pruning the weakest of the species: nature evolves animals, then man, then man evolves ideas, ideas evolve into plans for jet planes, then man develops real jet planes, then jet planes swallow birds. It's just basic evolution silly.
John_Chalisque
Guys Hot Tub Time Machine worked.
Just another second banana
Have you ever wondered why one side is longer than the other in that V formation? I have personally spent time studying this phenomenon and am now writing my paper explaining this titled "More Birds on That One Side".
I've never seen any study that DIDN'T claim more research was needed.
I've seen this comment suggested as the most important part of any scientific article. ;-)
Actually, I like to mention this to the folks on the religious side of the religion-vs-science "war". If you think about it, saying "further research is needed" is a clear, unambiguous statement that the writer doesn't know and understand everything about the topic at hand. This is a sign that the writer probably is actually a scientist.
Religious people, OTOH, already know everything there is to know about whatever topic they're talking about. If you question their evidence, they classify you as a heretic, because a revelation from their Ultimate Authority needs no evidence.
We see a lot of this in a more suble form in this forum. Most of the posts here are in one way or another discussing the claim that this research wasn't needed, because it was known decades ago. People who say that are basically religious, in the sense that they've accepted a theory on the basis of a claim by a supposed authority. But scientists aren't supposed to do this. Yeah, it's handy to accept claims tentatively, if the authority has a good track record so far. But claims of even the most trusted authorities are supposed to be open to challenge.
As others have pointed out, we have had very little actual testing of the various theories about how birds and other critters with flexible, flapping wings actually manage to fly. Almost all our testing has been with rigid, fixed-wing gadgets. That's interesting scientifically, and useful to engineers. But it shouldn't be accepted as an explanation of how birds or bats or insects get their lift.
Relying on untested authorities has a very poor track record, historically. We just had a new case pop up that has gotten a bit of publicity: Someone recently tested the medical benefits of the popular vitamin supplements. It turns out that, unless you have a specific vitamin deficiency disease and take exactly the needed vitamin, they're just placebos, with no measurable affect on health or lifespan. It was just another religious-style scam based on "reasonable" theories, but all it did was extract money from the population for no health payback. It's yet another good example of why we need actual scientific tests of things that "everyone knew years ago". The medical field in particular has a history of this sort of untested "everyone knows" belief system.
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
Some migrating birds fly in 'V' formations and are highly visible. Some fly singly and are almost invisible, unless you're purposely looking for them. Some fly in irregular groups, and are of intermediate visibility.
Corresponding to these multiple migration strategies, I'd expect there to be multiple solutions to the problem of "how do I get from $HERE to $THERE with minimum energetic expense?"
These dinosaurs have been facing the changing problems of survival in a resource-constrained world for about twice the period of time and perhaps three times the number of species that mammals - humans included - have, and I'd reckon it's a safe bet that they've come up with lots of solutions.
In fact, with the exception of the relatively short migrations of gnus and some other African herbivores, and some whales ... are there any mammals that have major natural annual migrations? I'm trying to think of examples. (Caribou/ reindeer/ elk : any more?)
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"