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New Theory on Water Strider Propulsion
capt.Hij writes "There is an interesting
article at the Christian Science Monitor about how water skimmers are able to move the way they do. This new theory debunks the previously accepted theory and answers why smaller, younger water skimmers are also able to move the same way as their elders: 'As he looked into the question, he adds, he learned that the reigning explanation leaves an unsolved puzzle: If these tiny insects propel themselves in the way many researchers think they do, then baby water striders should go nowhere fast.'" There's also a BBC story with pictures.
They move by using their mid leg pair as oars and the back pair as steering wheels. Previously, researchers thought they generated small waves, but baby water striders are too small to generate waves big enough to move on. The new research show that the waves are a biproduct of using the middle pair as oars, not the reason they move. Pictures here, same news in norwegian here.
Very good article on this in scientific american, if anyone is interested!
Hehe. Well, they did talk about making small robots capable of running on water in conjunction with the research. No practical appliances so far, but who cares about that.
The Independent has a related article here.
I want to drag this out as long as possible. Bring me my protractor.
My mother was raised literally on the river (towboat pilot Dad), and knows how to "scull" (propel a small boat from the stern using a single oar or paddle.) The oar stays in the water and does describe a circular or elliptical path. It's about the weirdest means of locomotion I've ever seen, and doesn't look like it should work. But I can vouch that it does.
I could never do it, although I was just a kid the last time I tried. Anyone here who can?
Everybody whose anybody knows waterstriders use anti-matter as propulsion.
All I know about water skimmers/skippers is they're a bugger to hit with rocks, unless you get a really big, flat rock and even then you mostly just get yourself wet and still miss the skimmer.
"Those who would sacrifice liberty for security deserve neither!"
a) It's in Christian Science Monitor
b) It's about skimming over the water.
Chances are, Jesus features in the answer.
A longer article mentioned a bigger strider they studied.
I found it amazing that the robot was half the size of the Asian giant water strider.
An 8 inch Water Strider might make a cool pet!
What would it eat? How big of a pond would you need? Does anyone have experience with these critters?
Row Row Row your bug, rowing down the stream...
But really though, if all it does is rowing, don't we already have tons of models that uses rowing? I mean, it's not electronic, but rowing's been around for centuries!
I'm not the devil.. just his advocate.
I think it's an interesting reflection on humanity when evolution can throw up designs that we can't properly understand even with all of our apparent science and technology (bees, water striders, the thought process). It just goes to show that for every fact or theory we think we know there are far more that we don't, which gives me great confidence in the progress of human science and technology over the next few thousand years.
Not really boring, but certainly not UT2K3 either. Personally I find these types of things fascinating. That's what makes me a nerd, nerkle or whatever, not my 1337 hacking skills (which I don't have anyway).
"We don't know what we are doing, but we are doing it very carefully,..." Wherry, R.J. Personnel Psychology (1995)
Well this is news for nerds and science is a pretty nerdy subject!
-- Karma Karma Karma Karma, Karma Chameleon - Boy George
It's magic!
The CB App. What's your 20?
They move because they put their faith in jesus and he spirits them along over the water on the wings of christ.
Damn dude, it said the CHRISTIAN science monitor.
You remember.. the people who don't believe in evolution? Or stem cell research? Or cloning?
... I've pondered how waterbugs move around on top of the water. In my naivete, thinking there could possibly be no connection between something that actually matters like a cure for cancer and water striders, I dismissed this ponderance for something shiny.
The shiny thing was a small robot that could possibly make use of this method of propulsion. Then I realized there were only 10 of us in the world and rejoiced as this great find was made public and made available to the popular geek culture. Now thousands of others can wish they had the required nanoseconds of their life back that was spent to dismiss this headline.
Speak truth to power.
Are water striders one of those bugs they have everywhere like flies/mosquitos/etc. We have them in oz, here in the UK, in asia and the US. Anywhere else.
-- Karma Karma Karma Karma, Karma Chameleon - Boy George
... is a bug!
Walking on water isn't hard. Everyone can do it - just make sure that the temperature of the fluid-to-be-walked-on is subzero.
I've been doing sweep oar rowing and sculling for years... It's something that anyone can do, but few can master. The blade (the oar) moves in a roughly ellpitical track in the water, over a very small range, as the boat is propelled forwards. The range of motion is dependant upon the skill of the oarsman, and how he/she appiles pressure to the stroke. Too much too soon, and you 'rip', causing turbulence, and allowing the blade to move excessively through the water... Too little, and the blade won't lock onto the water, and will just float through the water... Of course, this is neglecting balance etc., which is no mean feat in a boat some 5 inches wide at the waterline!
A few of my colleagues have been looking into the effects of surface tension in various liquids and you'll be amazed to learn what you can do if you have the right circumstances.
H20 doesn't have that much surface tension becuase of its low valency, but other liquids such as bromine are held together by strong Van der Waals attractions meaning that they have much stronger surface tensions. In one famous experiment at MIT researches showed just how strong the surface tension could be by placing a cat onto a large pool of bromine and observing that not only did it not sink but that it could also move abount (albeit with difficulty). Some people have suggested (tongue in cheek) that if Jesus could have introduced bromine into the red sea then that would explain how he could have walked on water.
All that glitters has a high refractive index.
So what you're saying is, you're a Christian troll?
Slashdot quality declines as the number of hot grits posts decreases. - Provolt's Law, Apr-09-2005
We need a "-1, No sense of humor" option.
The pilots of the reed boats they use to taxi between the floating Uros islands seem to use a similar technique.
The CB App. What's your 20?
for this bit of 'news'?
reminds me of going for the cookie jar only to find raison cookies!
caveat: it's early and my humor's warped to begin with...
People in cars cause accidents....accidents in cars cause people
the microorganisms that live symbiotically inside of me think of me as "God".
I would say that unlike parent post, the CSM is actually quite objective.
Go take a gander at the original BBC article with the photos. The one with the blue dye in the water showing the eddies created by the movement is practically a natural reproduction of Van Gogh's brushwork!
It's like having insects do impressionist painting. Truly beautiful. If I can find a high-res photo, I think I've got my new wallpaper.
Design for Use, not Construction!
It seems that we have a Christian source of information related to walking on water?
:-)
At least it is their own IP
Now: bugs walking on water.
Next up: evolution!
Somebody get that guy an ambulance!
The publication was founded by the cult Christian Science, founded by Mary Baker Eddy. I don't know that group's take on Intelligent Design, but I sure wouldn't be supportive of that group.
It's not the Red Sea, it's the Lake of Gennesaret.
;)
The Rea Sea was the one where the surface tension didn't hold up to the weight of the Egyptian Army
Just my E0.02.
Ooooohh Pictures!
---
When I grow up, I want to be a kid again.
Now this is a troll if I ever saw one. Bromine is the only liquid nonmetallic element. It is a heavy, mobile, reddish-brown liquid, volatilizing readily at room temperature. It is toxic comparable to chlorine. The surface tension of bromine is LESS then that of the water.
Cat (or any other live being) in a large pool of bromine has a life expectancy of a few minutes. And yes it would sink.
Please don't talk about Northern Ireland when you clearly have no comprehension of the situation here. It's not about religion, it's about a history of bloodshed, hatred, intimidation and suspicion, differences in politics and people who like violence. You'll hear the victims say 'I forgive them' while the terrorists drown on about how they want revenge and 'the war isn't over'.
No, faith is believe in the absence of complete proof; it can still have supporting evidence. Blind faith has no proof. Science itself requires a modicum of faith.
Not so! For you see, the cat can stay aloft as long as it still has lives to use. It would only sink and die following the expiriation of its last life. ;)
"Doctor" and "Bush". After the last few years, I have a lot of trouble visualizing that...
I am a viral sig. Please copy me and help me spread. Thank you.
Now all we need is to figure out how to make water have enough tension to hold a person. Hrmm...
- Nick Busey
www.pedalbmx.com
www.nickbusey.com
Yes, because force should decide every disagreement, right?
If the view you're presenting is so weak that it must be backed up by force of arms, doesn't that tell you something is wrong with it in the first place?
Probably meant Bromine added to water to increase the surface tension. Let me consult the Index to All Knowledge... Bah! Too many big science bloody PDF files out there.
One line blog. I hear that they're called Twitters now.
Sometimes it takes a lot of scientific training to work out things country people have known for a long time - digitalis, willow bark, cowpox, and all those interesting rain-forest rmedies the drugs companies are "patenting".
Panurge has posted for the last time. Thanks for the positive moderations.
Actually if you look at the guy's home page at MIT you'll see that he isn't spenging his life studying just this but fluid dynamics generally. He seems to have a particular interest in the fine points of stuff you see everyday like the fluid dynamics of wine in a glass and soap film
I suppose you might still consider this boring but I sort of like the idea of the brainy mathematician walking around looking at everyday things nobody (not even other scientists) really notices and saying "I wonder why it does that?"
Yes, I'm quite aware of that, which is why I put the 're' in bold. It was clear he meant Northern Ireland.
Let's face it, I live here and I know that most aren't and that the conflict has very little to do with religion. More to do with people's ignorance of a religion they claim to belon to and their fear of other cultures.
well; looks like these researchers know how to get attention. I got the news here in the Economist's excellent vulgarized science section
Misleading titles? Inflammatory blurbs? Keep in mind that Slashdot is a tabloid.
Genius. Someone should mod that up funny.
"too young", I meant, obviously. Gotta learn to preview...
Cut that out, or I will ship you to Norilsk in a box.
You remember.. the people who don't believe in evolution? Or stem cell research? Or cloning?
Good joke, but the Christian Science Monitor does an okay job of reporting science topics. It's sure above the level of typical popular media, leaving alone Fox News's special "They didn't land on the moon because NASA is the government" division. Glance at CSM's coverage of this fossil find. Hardly the whacko creationist extreme.
"Fundamentalism" isn't about divine morality. It's about human authority.
Well, I may never understand all the cultural references in Miyazaki-san's Spirited Away , but at least now I understand what Rin was doing in the scene where she is moving a barrel-shaped boat along, seemingly by doing nothing more than twisting what I thought was a rudder.
"Sculling" -- my vocabulary word of the day. Thanks!
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
I thought you were making a joke since it;s the kind of thing that people usually say about the Brits. And most people down South couldn't care less about whether the North is 'reunited' or stays in the UK. The Irish government certainly isn't trying to forcibly annex land, so it can't actually be imperialism.
Thanks for pointing that out. I missed it the forst time, but it definitely is beautiful. Good call!
"Curiosity killed the cat, but for a while I was a suspect."- Steven Wright
water boatmen are not water striders
Suchetha
learn from yesterday, plan for tomorrow, party tonight
or one out of three ain't bad
OH YEAH, Christians have so many problems with bias and prejudice against them in America! Poor Christians.
I disagree. I would say that what you describe is not faith but trust. If you have some bit of proof, you are trusting that bit to hold you through the unknown. Religion exists in that unknown space where truth can not be grasped. We are getting off subject. Maybe someone will start a post about God and science where we can talk further.
No matter how subtle the wizard, a knife between the shoulder blades will seriously cramp his style.
It's interesting that losing your child by choosing a solution other than medicine is "criminal", while having your children die in the hospital is perfectly acceptible.
.sigs are for post^Hers.
My hope is that one day we can have a story submitted from the CSM that doesn't generate volumes of insignificant chatter of over the name of the newspaper.
You don't hear constant blah blah about the state or city of New York every time someone mentions the NYT. People tend to focus on the story. What a concept!
.sigs are for post^Hers.
I like this comment. It sums things up pretty well regarding people and religions.
It goes something like you stated: I don't know anything about religion X, but I disagree with them.
Brilliant. At least do yourself a favor and research a religion before you decide it's wrong. That goes for any religion.
.sigs are for post^Hers.
This is easy. Go to Egypt, and then go down the hole at the far left side of the level. Hiryu will find the Aqua Boots there. ...Sorry, NES flashback.
Why do you assume that religion cannot have any evidence going for it? For something claiming to be the absolute truth, I would expect a bit of evidence to back it up and I see evidence for Christianity. Is it 100% proof? No. Does it leave room for doubt? Yes. But there sitll is evidence there.
There's only one problem, that made me twitch at the end. If there's "no bias" there should be any reference to million of years of evolution. Near the end of the article, out of nowehere they state that "over hundreds of millions of years, they have evolved the ability to sense just how much force to apply"...
I think you're reaching. If the article was about opposing viewpoints over creationism/evolution, then I would expect to see points from both sides included in the discussion. In this case, however, the article is just reporting a new theory in biology, and I'm sure you realize that the field of biology has pretty much accepted evolution as the most probably theory. In some cases, I've read that since some fast forms of insect evolution have been obvserved on the month and year timescales, that as far as science is concerned, evolution is all but proven. Certainly it is the generally accepted explanation in biology.
Conversely, if the article were about a priest coming up with a new theory of the magical way that a water spider moves, I'm sure the writer would assume you knew that the priest was basing his new theory on the assumption that God created the universe in 7 days, or whatever.
Overall, I think that this is not a good article to judge journalistic bias by, because it's really just reporting the progress of research, instead of covering something more controversial, such as differences in political or religious beliefs.
The best type of article to judge bias would be if they covered a debate between a liberal and a conservative. If they started to editorialize, or choose sides, or whatever, that would be your obvious sign of bias. Also, if they chose their sound bites to only make one side look good, that's also bias.
"I have never let my schooling interfere with my education." - Mark Twain
Wow, how stupid can you be to read an article about walking on water from Christian Scientists? I'd rather read about Britney Spears. I'm so intelligent and tolerant and stuff.
IMHO, if you're giving your opinion unasked, you ain't humble.
Your argument is wrong. "Trust" is not belief with evidence; it's the capability of acting on a belief. Amount of evidence and level of proof are irrelevant. I trust the chair I'm sitting in; I have faith that it'll hold me. I also have a lot of evidence. I trust my coworker (that one over there); I have faith that he will do what he's said.
Faith is a close synonym for trust, even in fine detail: for example, if I say I trust that chair, I may never sit in it; if I say I have trust in that chair, it means that I sit in it. Having faith _that_ something will happen is likewise different from having faith _in_ something or someone.
-Billy
From my point of view. My background is in fluid mechanics, and even though I've only obtained my master's, I couldn't have told that scientist where the momentum was transfered.
:(
The same thing for aircraft: tip vortices and a bound vortex on the wing alter the direction of the incoming air, which changes the air's momentum and provides lift. And all that happens because of friction between the molecules of air on the surface of the wing, and their neighbors directly above them. Then THEIR neighbors directly above them, and so on until you get to the overall flowfield.
And when you get to the tip of the wing, the downwash pulls the air past the tips into a vortex.
Those scientists that study these kinds of things would do well to actually study vortex dynamics (Kelvin's theorem would have told them the answer!). They would rather try and reinvent the wheel though.
Oh come on... are you calling into question the veracity of the famous MIT experiment? How about some facts? Bromine has a density of 3.12 g/mL--over three times that of water. People have no problem floating in the highly-saline water of the Dead Sea, which has a density of about 1.2 g/mL. So no, it wouldn't sink.
No, the general feeling is that all religious people are morons, christians are just the loudest and most common (locally) so most of the North American anti-religion sentiment is expresses as anti-christian sentiment.
Nothing personal, all those other religious people are kooks too.
If christians would have the decency to die off, like the followers of the norse religions, we'd look at christian beliefs in a tolerant way, like most people think of greek myths as funny stories, not silly examples of what real people were dumb enough to believe.
BC and AD are reminders that right now, there's a huge number of droolers out there who actually believe in this stuff. That's really annoying. Thor and Odin aren't reminders of this because nobody believes in them anymore.
Trust me, you'd be just as ridiculed if you were a muslim, or anything else.
> Oh come on... are you calling into question the veracity of the famous MIT experiment?
What MIT experiment?
> How about some facts?
It is much harder to me to prove that no such experiment took place. How about YOU provide some facts?
> So no, it wouldn't sink
I stand corrected. It would not sink because of buoyancy. But the pour agonizing cat would certainly break the bromine surface and get wet (unlike strider on a water surface), which was the point of the parent troll.
Btw, I have handled pure bromine in a lab. It is a nasty stuff. A colleague of mine ended up in the emergency room for inhaling just a whiff from 1 ml vial. A large pool of Br and a cat thrown into it walks, give me a break!
Actually, it's natural selection which has been overwhelming proved. It's the addition of genetic material to the gene-pool which is an iffy thing. Nobody disagrees that it can be lost. The media's popularisation of the term 'evolution' when 'natural selection' is actually the correct one is partly to blame for this whole misconception.
-1 Overrated? Ooo, we have a Christer with mod points...
Slashdot quality declines as the number of hot grits posts decreases. - Provolt's Law, Apr-09-2005
Reminds me of a few uni students I knew...
(In case it is a local vernacular - "sculling" is a colloquial expression for downing ones drink without in one go).
Q.
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and I'm sure you realize that the field of biology has pretty much accepted evolution as the most probably theory
:)
but in an unbiased article, I wouldn't expect to see a point that didn't need to be made, that is known to presently still be on the debate table. The article is talking about a breakthrough in research which finally explains, in good scientific method, why something works with a creature. What does millions of years have to do with? And why does it only make one appearance in a next to last paragraph?
That's all I'm saying... the article would have been just as good without that comment, no less scientific, no less informed. But now we know that the writer believes in evolution, knowing that there are still other viable answers out there (viable as in not disproven theories) just as evolution is still a theory, though widely accepted as fact (yet still a theory). If he hadn't written that, he wouldn't be viewed as believing in one thing or another... just reporting on the facts at hand.
Everything in the article is believable and factual. But the writer cannot prove that it was millions of years that brought this about. So leave it at the discoveries, and don't dabble in anything beyond his reporting abilities. Leave the 'why's, 'when's, and 'how's to more scientific research...
(sorry, just a little miffed that my last post got a -1 overrated