Why Do Flamingos Stand on One Leg?

[@SciShow]

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[@RMSLusitania]

amogus

[@RealSlowLike]

You forgot that they also use the raised leg as a counterweight to their long neck. You could see this with the video of the chick where it moves the raised leg to counter it's head.

[@Grim712]

Came here to mention this also!

[@undecidedgenius]

Now I want to know if they switch leg or is one side dominate.

[@tessat338]

Annnd now so do I.

[@Gengh13]

Jeff would say they should switch to prevent muscle imbalances.

[@gretchenharris6640]

I believe they are probably left leg dominate like most other animals besides people. I don't know for sure though.

[@jaketyler7088]

@@gretchenharris6640 Dominance and stabilizing tend to be different. Most humans would kick a ball with their right leg, but they would be balancing on their left, like when people tend to jump from their left leg and land on their right. Water skiers tend to drop their right ski to balance on their left because that's the leg they balance on when kicking a ball.

[@gretchenharris6640]

@@jaketyler7088that makes a ton of sense

[@ociemitchell]

Because if they lifted that leg too, they would be hovering.

[@warrenarnold]

😅😅🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣oh Mitchel i told you stop smoking that thing mahn

[@pbezunartea]

@Ocie Mitchell: _Because if they lifted that leg too, they would be hovering._ 🤣🤣🤣🤣🤣🤣 Brilliant!

[@ReflectedMiles]

I thought the answer was always, "To get to the other side."

[@666Tomato666]

You want your dad card stamped, or it's already full?

[@ambert.3792]

the very opposite of loafing.

[@danielm5535]

“This test flamingo is named Bernie. We only have the weekend to experiment with him.”

[@LuinTathren]

I so hate that movie. My name is Bernie.

[@hunterflowerson4460]

Rumor has it he wants to give us healthcare too

[@tessat338]

That one joke was better than the whole movie AND its sequel.

[@Primalxbeast]

@@LuinTathren Do you smell bad and steal Polaroid cameras from families visiting the biggest ball of twine in Minnesota?

[@NoThankUBeQuiet]

@@LuinTathren Were you born 70?

[@carissstewart3211]

🥳: "So Fred, I hear you're an ornithologist. Sounds fascinating. What did you do today?" 👨‍🔬: "Well, I manipulated a flamingo carcass to see if it would stand up on one leg... you know, like a lawn ornament." 😟: ... 👨‍🔬: "It's okay. It was dead when I found it."

[@becauseimafan]

😆

[@arthas640]

Flamingo widow: 😢

[@EnvisionedBlindness]

*"Why is the captive flamingo not pink"* Because the aren't naturally pink. They turn that way because of their diet.

[@OrigamiMarie]

I know this is very unlikely, but I want it to be possible to feed different things to flamingos and turn them purple, lime green, and antifreeze blue.

[@SongbirdOfficial]

Also it might have been a juvenile, they're born with grey feathers, since of course they haven't eaten the crustaceans that turn them pink yet :P

[@katyungodly]

It's a baby flamingo

[@fleezyp]

@@OrigamiMarie certain algae can do that btw, there are glowing blue algae they could technically eat and become glowing flamingos

[@AskMia411]

@@fleezyp That is wonderful information that i didn't realize I needed, thank you

[@vanessafrey3557]

"you can't even to that without... eughh" i love this guy

[@apextroll]

I didn't think it was possible to kick the bucket on one leg.

[@TheTexas1994]

Stand on one leg. Kick the bucket with the other

[@warrenarnold]

Or better, like a flamingo, stand on one leg after kicking thr bucket

[@CallMeMimi27]

@@TheTexas1994 that would mean using 2 legs. What you need to do is stand with one leg, jump, kick the buckey mid air and land with the same leg

[@pierreabbat6157]

But can Hungarian flamingos throw the boot up from one leg while standing on the other?

[@pentalarclikesit822]

"Physics of Flamingo Joints" is officially going to be a song title.

[@avielp]

My bext band name

[@supersonictumbleweed]

And now time for the newest recording from the rising star! Physics! By Flamingo Joints

[@urbannanni5864]

Joints, as in where they are bendy, or what they smoke, or perhaps it is where they hang out after work for a beer with the guys?

[@JustMeJH]

Cool that you have a policy to update and review and/or remove videos rendered inaccurate by time. I was wondering about that.

[@bland9876]

I think they should leave it up as a science History lesson and they could put a thing saying that it's outdated now with a link to the new video. If you do still let them put intros and outros on their videos they could have put an intro to update but oh well

[@icedragonair]

Yes, I feel like they should add a preface to the old video explaining its wrong and put it up again. We can learn as much from our wrong assumptions as we can our correct ones. Also it is always worth remembering that throughout our history, we have believed in things, sometimes for a very long time, that made sense but were simply not true. Its good to keep a record of our learning progress. There is nothing wrong with being wrong, but it can be dangerous to forget that we were wrong at some point and fool ourselves into thinking we always had the right answers.

[@barneylaurance1865]

@@icedragonair Adding a preface to the old video would be a lot more expensive than just taking it down - and even then someone might start watching in the middle and believe what it says, so they'd still sort of be publishing misinformation. Maybe they'd want to put a caption over the video the whole way through, but then what if someone blind listens to it? Best make sure at least the video description and title are updated to make sure it's clear that it's no longer considered good science. The old inaccurate science shouldn't all be removed but maybe it shouldn't be available on a science channel. If history of science researchers want to use it then they should be able to contact SciShow and ask for a copy.

[@AlienXtream1]

changing the title to indicate its outdated and setting to unlisted (with a link to it in this video's description) is also potentially an option. but i do think taking it down was the best course of action as if the video were ever embedded anywhere it could still circulate the inaccuracy.

[@icedragonair]

@@barneylaurance1865 thats a lot of ifs lol. If people are watching it in some weird way honestly then even if the video is accurate you can be misinformed. There is so much wrong info out there but also info that is factual but presented so out of context that people come away with completely the wrong idea. I dont think the worry about an old vid (which basicaly WAS scientific at the time) that got outdated is such a big concern. As for expense i guess. I mean youre not exactly wrong, its just such an edge case and were talking about flamingos, not some lifesaving info that would kill someone if misinterpreted. As the other guy said, if you reupload the links vanish, and a 30 second intro in the begining isnt that expensive. Its an interesting bit of knowledge I think thats all, I wanna see it, see what we used to think was the answer. Not from a science history perspective, but a "if this is wrong why did we think it was right?" Learning prespective. Like we dont go hunting down sex ed tapes from the 50s cause god forbid someone doesent realize theyre from the 50s right? You can find those on youtube too. Theyre completely innacurate, but we dont erase them from existence. We learn from our mistakes, cant learn if we just delete them all or relegate them to historians.

[@breadbun1975]

“Which we are now taking down off the internet” I can always trust Scishow to give us the best facts & honorably remove posts when new information comes out ❤️ I love Scishow

[@zockertwins]

Yes like that Damascus video that was so full of mistakes and misleading arguments they took it down.

[@AkaiAzul]

True, but now I can't look back and re-experience the old video.

[@craigrobbins2463]

It would be better if they put a caption at the beginning admitting their new found knowledge, linking the new vid, and keeping their content up.

[@Cr3zant]

@@craigrobbins2463 The reason they delete it is to minimize the spread of misinformation. If they kept the video up and just put a caption (a system youtube long removed btw), the vast majority wouldn't read it and the misinformation would continue to be passed along.

[@zockertwins]

@@ArawnOfAnnwn agreed

[@thomasgoodwin2648]

Seems to me the position of the raised leg also helps to move the center of balance more towards the rear to offset the weight of the neck and head. In addition the movement needed to maintain balance is more easily accomplished if the swinging weight (in this case the raised foot) is at the end of the lever rather than close to the fulcrum, allowing less drastic needed motion to maintain balance, and thus conserving energy.

[@wonderwang1585]

It’s easy to understand ballerinas standing on their toes can serve energy too.

[@julianshepherd2038]

They fall over if they lift both

[@AskMia411]

I just imagined that instead of just dropping straight down, they picked up their legs, and THEN tipped over wily coyote style XD

[@elizdonovan5650]

😂😂😂Good point. 😂😂😂 ☘️🌝🌲

[@maureenu3047]

😄 Mom: What did you learn today? Kid: Dead flamingos can stand on one leg. Mom: ~starts hiding all the sharp objects~

[@سويكتبنراضي-ي3س]

Lol

[@eljanrimsa5843]

So the real question is: Why do flamingos have two legs?

[@emmamemma4162]

Walking

[@yoursnatchedweave641]

the realer question is: how did people miss the joke

[@Itsjustme-Justme]

Wind the tape of evolution forward a few million years ....

[@PabloSanchez-qu6ib]

Because they can't count.

[@brianisme6498]

@@yoursnatchedweave641 idk I laughed at the walking reply. It’s probably not entirely serious either

[@LolUGotBusted]

I have heard that flamingos regularly stand in rather caustic water. I would imagine resistance to it is best earned one leg at a time.

[@Javier-mc4pc]

YES, why is no one pointing that !

[@SoWhat1221]

This was my assumption, too.

[@GPCTM]

they haven't address that point - I mean: which leg? do they alternate?... (have they?) So, those "scientists" seems to be not that clever.

[@jimnavarro6859]

I always thought I knew but now I know I know thank you

[@TheTexas1994]

That old episode of Scishow with the Flamingo is a throwback

[@afhdfh]

Now the question remains: Why did the evolve joints that make it easier to stand on one leg?

[@ValeriePallaoro]

They need to sleep and have long legs; asleep on both legs is unstable; you'd have to sit on a nest to get a good sleep; and that leaves you open to predation. So those with joints that are close to letting them do this are safer because they can sleep on the lake. These might be able to pass it on; after a few generations, it'd be the thing.

[@afhdfh]

@@ValeriePallaoro Sounds reasonable. But I still don't get why sleeping on two legs is more unstable than on one leg. Evolution-wise, this doesn't really make sense to me.

[@clairefuzipeg1983]

"Must be an interesting question of "what do you do?" at parties" XD

[@sweepingtime]

Mm yes I didn't need to see a dead flamingo like ever.

[@yukaiqian9673]

My favorite part of this videos is that "loafing" is an actual formal term.

[@simplicitylost]

The flamingo 🦩 next to me was like: “Tacky?… TACKY?!” She’s now on a first-class flight to Montana to find you. (Yes. She could’ve flown herself. But what can I say? She likes to indulge and experience the finer things in life.) So if you see a rando flamingo in Montana, you better walk the other way because she lookin’ for you, Hank!

[@danondler8808]

I love the Occam's razor of this. They stand on one leg because it's the easiest thing to do. Thanks SciShow. I am such a fan of this channel.

[@Puffycheeks]

But which LEG?! Do they switch legs or are there lefty and righty flamingos?

[@violet_broregarde]

I love the writing starting at around 1:28, the tone is perfect for the absurd subject matter

[@zalphinian]

You had me at flamingo!

[@kororopocoro4935]

Scientists: why flamingoes stand with single foot? Flamingo: because I can.

[@twothreebravo]

You say "scientists" stood dead flamingos up on one leg when we know it was probably specifically the Grad Students given that task.

[@domomitsune5920]

My parrot does this as well. I've seen my uncle's chickens do this as well. I really didn't know why birds do this. I thought it's just something peculiar that birds do.

[@virglibrsaglove]

Now this makes me wonder if the non-avian dinosaurs did this, too.

[@lukabudimir7233]

I have found the perfect video to watch while eating and then he shows scientists playing with the flamingo corpse

[@officialdislikebutton5566]

So they don’t stand on the other Thank you, I’m here all week

[@kateclark7250]

Stand on one leg post mortem? I couldn't stand on one leg now.

[@vladekvik2228]

I've observed parrots sleeping on one leg too. I think it is part of being comfy for a bird.

[@hdwnkt]

"propping dead flamingos back up on one leg" oh no... follow up questions, do they always use the same leg?

[@urbannanni5864]

If they're dead, I'm assuming that they do indeed use the same leg. Perhaps it's because ITS DEAD.

[@kindlin]

@@urbannanni5864 Stupid non-answer avoiding the actual good question.

[@erikzellers2925]

@@urbannanni5864 Nah, it is just pining for the fjords.

[@urbannanni5864]

@@erikzellers2925 omg, I haven't heard THAT in a long time!

[@johnbeamon]

01:30 is the culmination of all the years of SciShow content creation and the combined educational backgrounds of all its hosts. This is the statement all our lives have led to up to this point in spacetime.

[@patrickhannon4217]

I really want to see the outtakes to this LOL, seemed like Hank was having a bit of fun here

[@mascadadelpantion8018]

This is one badass channel!!!!!!!!!!! I will always be subscribed and I will only support this channel for this video alone!!!!!!!!! It takes a big person to admit when they're wrong especially on a public forum. This just makes this channel much more credible. To even openly say that they accidentally believed something that was just not true

[@calvinthurston1441]

Thx for the update!

[@JayVBear45]

Now THAT'S how you do "a science"! You do your best with all the available data from observation, make a hypothesis, do more observation and research through collaboration and peer review, state your conclusions to form a theory, find out that the theory is flawed, scrap that theory and search for better data through further experimentation/observation/ peer participation until you arrive at a more viable/sensible theory. Admitting your mistakes is NOT a weakness - refusing to correct them or attempt to correct them IS! Bravo SciShow!

[@jessicaevans7847]

Finally get another Hank video, and it's freaking flamingos.

[@GreebleClown]

1:49 To bird owners this is normal, most birds sleep or rest like this.

[@seanferguson5460]

OK, so one leg standing requires less energy expenditure. That's an advantage, I suppose. But is there a stronger evolutionary advantage? For example, would a flamingo's water-dwelling predator or prey be less likely to identify a meal or a threat that has only one leg in the water?

[@DefnitelyNotFred]

Hmm evolutionarly speaking, less energy consumption means less need for food. Also flamingos are bottom feeders, they eat small crustaceans, algaes, etc, so there’s no real danger of their “prey” escaping haha

[@seanferguson5460]

@@DefnitelyNotFred Given. Still, if it were that much of an advantage I'd expect to see many more bird species doing it. The tall ones, at least.

[@DefnitelyNotFred]

@@seanferguson5460 hmm not many birds sit on the floor to eat, pretty dangerous against predators. Flamingos circumvent this by having a massive flock, not very common on other bords either. Some may be eaten but most will fly away unscathed. But this might an advantage given the types of predators flamingos have, other will have different pressures

[@ken481959]

A much better balance for them while feeding. The other leg acts as a counter-weight for the head and neck while feeding with the head upside down. By moving the position of the leg in and out away from the center of gravity, they can maintain balance effortlessly. Like a construction crane used to fabricate skyscrapers. They can also swivel on one foot, like a crane on the center.

[@virglibrsaglove]

That does make sense. Two identical legs might look more obvious. But one could look like a reed or something.

[@Loooam]

Thank you Hank

[@prettypic444]

I remember when I was in youth group, we did a fundraiser where we "Flamingo-ed" church member's lawns. We would sneak plastic flamingos onto church member's lawn, and said members could pay $5 for us to remove them or $10 for us to send them to another target.

[@dannyleung2796]

This video explained the "how" but not the "why" flamingos stand on one leg.

[@cezarcatalin1406]

Why: evolution and pink magic It’s always that pink magic that’s getting into things and it’s making them weird isn’t it ?

[@slwrabbits]

Uh, conservation of energy? It may be a simple reason, but it's a very powerful one.

[@trikers471]

@@slwrabbits No, they conserve energy, because they are adapted to stand on one leg. That doesn't mean that they conserve energy compared with other birds, who stand on two legs. It just means that they are well adapted to standing on one leg. If standing on one leg conserves energy in general, why don't other birds do it?

[@WanderTheNomad]

@@trikers471 Probably because of the difference in food source. That's just a guess though.

[@DeadlyPlatypus]

@@trikers471 Muscovy ducks also do this, but they don't share much in common with flamingos.

[@thederpysqueege]

I love this channel

[@diamondjub2318]

they like to work out their legs, but you can't get *RIPPED* by using both at once

[@BRUXXUS]

I would think it'd take a lot more energy to keep the raised leg held up than standing on two locked legs. 🤔

[@jessicalindsey4855]

I love that you updated with new data AND you are removing the old video. Yay! Science!

[@yelljal2764]

Fun fact- Lawn Flamingos where actually invented in the town of Leominster in Massachusetts.

[@Rockmaster867]

I watched this whole episode while standing on one leg

[@DrJALAGHARI]

Thanks for sharing such an amazing information.

[@debrawondergem1528]

Q: why does a flamingo stand on one leg? A: because if they lifted them both, they would fall down.😂

[@Goldenrod6901]

"Which we are now taking off the internet" Fantastic to learn Scishow respects accurate knowledge more than views 👏

[@TheKastus17]

At the MN zoo, there are ducks that share an area with the flamingoes and often copy the one legged posture and it looks so cute

[@eliletts1680]

Wow! I just learned something new! I would have never guessed that dead flamingos would be able to stand at all! 😯

[@lajya01]

When you think about it, when you have to stand in line, more often than not you're putting way more weight on one leg than the other than switch from time to time.

[@RyanGoertz916]

Hank looking sharp today

[@bandgeek9723]

But what was the evolutionary pressure that led to this adaptation?

[@Takesis]

Sleeping on an airplane of course!

[@Okamy1993]

Or the possibility of getting bigger due to less energy consuming stance but same prey rate... Females prefer bigger birds because they are stronger etc etc so they get more Offspring....

[@Okamy1993]

It could even have something to do with the way of hunting those crabs in shallow water... One still leg is probably creating less water movement, so the prey comes more near the bird... that includes the duration of still standing like when you go fishing maybe... Those with that one leg technique get more calorories in, get bigger and get more females to mate. Those with more efficient one leg technique will domonate and propagate populationwise... I hope those assumptions can give you some viewpoint concerning your question... Greetings from Germany

[@JavenarchX]

They didn't know the answer. I think it may have been to be less exposed to the caustic lakes that they have evolved in.

[@trikers471]

@@Okamy1993 Great suggestions, but the point, I think, is that the video shouldn't have that title, if it doesn't answer that question.

[@Matthew-pi7jx]

I often will fall asleep standing in the shower for a few minutes. I have slept for hours sitting on the toilet.

[@TheCimbrianBull]

I've fallen asleep on the can quite a few times myself but I've always woken up because my legs were hurting.

[@THETRIVIALTHINGS]

I wish SciShow would do more of these instead of the other ones about virus and stuff. This stuff is more fun and interesting to watch.

[@minnymouse4753]

Talk about eyes the cells that transmute light are facing away from light and nerves would be blocking light maybe the retina cells transmits color. Different unofficial recognized cells transmits general light

[@safaiaryu12]

This video was not what I was expecting.

[@JohnDrummondPhoto]

This one-legged standing pose seems limited to shorebirds and waders. I've seen ibises, herons, gulls, ducks, oystercatchers, etc. all standing relaxed on one leg. On the other hand, birds that can perch on tree branches don't do so on one leg, and they don't have to. The tendons that loop behind their ankles and extend into their toes lock their feet into position when perched, so they can hang onto a branch without trying to. Birds are apparently all about saving the energy that they really need to fly. I presume then, that's why ratites don't stand one-legged either. It saves them nothing, so they just flop down on the ground.

[@AustiuNoMatterWho]

I appreciate the update

[@jaredhamon3411]

Do not delete the old, simply add a pinned comment at the beginning to explain the change. We do not delete old science because it was wrong we use it as a source to track our changes and understanding.

[@anthonyhewitt9397]

Well then its just more bad info on the internet. What if people only see the old and not the new.

[@zacm.2342]

There'd be some people who wouldn't read the comment for whatever reason though. I'd rather it stay up too, but they're very much about accuracy here. Just minimising the risk of misinforming people. Besides, SciShow doesn't need to keep it up anyway, that old idea will still be accessible elsewhere.

[@warrenarnold]

Yeap, i think scientists should never be ashamed to be wrong. Science is a continuous process. They shud have edited the title on the other to prefix [INCORRECT, reviewed]

[@brefasdra]

Only problem is there are people that won't read the comment, would be better to change the title and thumbnail. But even that is not perfect, KZbin doesn't really support corrections very well, best bet is to take it down to prevent misinformation.

[@barneylaurance1865]

We delete it from some places, we don't delete it from others. It all depends on contexts. If we're publishing a new edition of a science textbook then we absolutely do delete the things in the previous edition that we no-longer believe. But we don't burn every single copy of the old text book. Some people will have downloaded the old SciShow video and we won't force them to delete their copies.

[@Spacedog_42]

Do flamingos switch legs or do they stand on the same leg all the time?

[@Nilsy1975]

Oh, I always thought it was because their legs got wet* and that might cause their legs to rot. That they would keep changing their legs, that is switch from one to the other so they didn't rot. Because they were standing in a lake.

[@LukeCampbellBrennan]

I saw two canada geese standing along a riverside in Pittsburgh each on one leg. At the time I assumed they were just doing a flamingo thing, and now after learning about the necessary skeletal adaptations, I worry those were just one-legged geese.

[@kentarouification]

Scientist: We study by using a dead flamingo. Me: What dead flamingo? Scientist: This dead flamingo.

[@AianaRaven]

Alright. I was eating when I put this on. For some reason the dead flamingo wasn't doing it for my appetite.

[@victoriabungart4330]

Flamingos are my favorite animal so thanks for this video 😍

[@swastikbiswas8293]

Now I know why but can't go to sleep (3 AM )know they used cadaver and using as rag doll for experiments

[@jonathanseibert8832]

Flew thru ATL the other day. Went to the ONLY smoking area there, in F terminal. While smoking, there was a super friendly little pigeon hanging out with me. He almost stood exclusively on 1 foot. Maybe a "dress for the job you want" situation? He just couldn't turn pink lol

[@nickverbree]

I have so many follow up questions: WHY aren't they as stable when on two legs? What evolutionary pressure was there for the bird to evolve these crazy joint structures? Was it happenstance that one flamingo one day went "hey standing on one leg is easier"? Do other birds have the same behaviours and join mechanisms?

[@pamelamays4186]

Propping dead flamingos to see if they can stand on one leg. When science gets dark. Dead Flamingos. Metal band name for sure.

[@robertsnearly3823]

The next time somebody pokes me on Facebook, I'm gonna see that video in my head. Poking a dead bird to see if it will fall down. All in the name of science. Smh. giggle

[@chromeorihara1949]

I feel this answers the question of why flamingos can stand on one leg rather than why they stand on one leg.

[@WanderTheNomad]

2:00 3:35

[@RMSLusitania]

Someone send a link to the old one

[@TRDPaul]

When I saw the video title I was sure there was already a scishow video about it and I was right

[@SteamingBurito]

Plastic pink lawn flamingos were invented in Fitchburg, Massachusetts. Right near my home town of Leominster.

[@demetrinight5924]

Nature is weird yet fascinating.

[@thewonkiecoin9504]

Just a note. The old flamingo video is still within the bird questions compilation. So some people may run across it.

[@craigslistreplies3485]

Can you do a show about bras? Years ago there was a study that said bras actually cause sagging but many say that study was flawed.

[@chromosome2661]

I always imagine in a few thousands years, flamingo will evolve to have just one leg

[@andrewsuryali8540]

They still need both legs to do the takeoff kick.

[@marksusskind1260]

Rest in Peace for all those flaminstops.

[@Eneov]

Nice blazer Hank. I want a blazer now.

[@TraphouseTCG]

S-tier episode

[@Yaxchilan]

Exactly the vid I wanted.

[@nimbly1693]

I like that you admitted that you were wrong. "The most elementary and valuable statement is science, the beginning of wisdom is, I do not know."

[@Amitdas-gk2it]

TY ☺️

[@route2070]

This video took me a lot further then I thought it would when I clicked on it.

[@stevematson4808]

If you can get close enough You'll hear them say "look what I can do"

[@corlisscrabtree3647]

Thank you

[@commonconservative7551]

i know why----any hunter hesitates prior to taking the next step , because the hunted game might use a quick getaway action that dictates the flamingos next step direction or attack action

[@NomzNoodle]

A lot of birds sleep with one leg tucked up tho

[@davidprodigy5833]

Great video

[@GearHeadedHamster]

I'm confused. While Hank gave a great explanation of the mechanics behind how a flamingo can stand on one leg,, he never gave an answer as to why they stand on one leg. He only said that it wasn't for heat conservation. So what IS the evolutionary pressure that drove flamingo to go from bipods to monopods?

[@DeliveryMcGee]

He did give an answer -- two legs is less stable and less energy-efficient.

[@GearHeadedHamster]

​@@DeliveryMcGee I'll agree that joint locking is an extremally energy efficient adaptation that can be found in many animals. From quadruped horses, to biped humans, to even hanging bats. What I don't get is how a one legged joint lock can be 𝘮𝘰𝘳𝘦 efficient then a two legged joint lock. As for the stability thing, It seem more like a symptom of one legged evolution, rather then the cause. Else we'd see more animals tend towards one leg stances. Edit: never mind on that last thought... I just remembered that Canadian geese do it too, as well as several other birds. It seems one leggedness is more common then I thought...