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.

Dancing legs

[Jarlsberg (643324)]

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 [nature.com], same news in norwegian here [science.no].

Wrong.

[by Anonymous Coward]

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?

Re:Wrong.

[RobinH (124750)]

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?

That would certainly be most people's first impression, but I find that the CSM is probably the *most* objective reporting I've ever seen to date. There doesn't seem to be any particular bias that I can see. I'm glad I found the CSM, and I really enjoy reading it, even though I'm agnostic. I highly recommend everyone take a look with an open mind.

Re:Wrong.

[Gzip Christ (683175)]

That would certainly be most people's first impression, but I find that the CSM is probably the *most* objective reporting I've ever seen to date. There doesn't seem to be any particular bias that I can see. I'm glad I found the CSM, and I really enjoy reading it, even though I'm agnostic. I highly recommend everyone take a look with an open mind.

I second that. Compared with the mainstream press, it's utterly amazing how objective the Monitor has been throughout the whole water spider controversy.

Re:Wrong.

[revery (456516)]

You remember.. the people who don't believe in evolution? Or stem cell research? Or cloning?

Yeah, those three are the same.

Do you mean that they don't believe cloning is possible, or that they don't believe evolution is moral?

--

I don't believe in you...

Re:Wrong.

[JonathanBoyd (644397)]

If you can have miracles, that doesn't mean that you can't apply science the rest of the time. The two aren't incompatible.

Re:Wrong.

[revery (456516)]

I should clarify. I do believe God is a being and not just a creator of forces. Larry Wall described [slashdot.org] it much better than I can in his answer to question #7 in his Slashdot interview. One part I'd like to modify or add to concerning Larry's statements. He makes the assertion that "God is good to people who really look for him." I agree with that statement, but it's necessary to define what "good" is. One of the problems about discussing an all-powerful God and anything his existence affects (which is everyth

Re:Wrong.

[JonathanBoyd (644397)]

You do realise there are plenty of Christian scientists, right? And that the overwhelming majority would have no problem with natural selection, which very obviously happens, but instead differ over whether or not we are the result of random genetic mutations, which quite a few non-Christian scientists are sceptical of as well.

Now, as for stem cell research and cloning, what do you mean by 'don't believe in'? They accept the scientific theories concerning them, but think they are morally wrong. A different

Re:Wrong.

[overunderunderdone (521462)]

I think you may be misunderstanding where the name "Christian Science Monitor" is coming from. This is NOT a journal of science put out by Christians (creationist or otherwise) The CSM is a paper that was founded by a religous group founded in the 1800's known as the "Christian Scientists" or more formally "The Church of Christ, Scientist". The group is often considered a cult and is pretty much disavowed by both christians and scientists (and presumably christian scientists that are not "Christian Scientists"). From time to time they get in the papers because at the core of their beliefs is faith healing, or more accurately that there really is no such thing sickness anyway, so they will refuse medical treatment for themselves and their children.

The Christian Science Monitor itself is a highly respected paper and while I think it is still officially owned by the church I think they have a hands off approach to running it and if they are using it for "evangelistic" purposes they use it by putting out a very high quality paper that by it's quality lends credibility to their group rather than using it as a polemic tool in itself. It's seems it's sort of like the Moonies owning the Washington Times rather than like an official organ of the church.

Re:Dancing legs

[B'Trey (111263)]

Thanks. I absolutely HATE articles like the one linked to in the story. In essence, it says "There was a previous theory which doesn't work. But we're not going to explain what the previous theory was because you're probably too stupid to understand it anyway. Now, there's a new thoery. But you're too stupid to understand it too."

Re:Dancing legs

[Jarlsberg (643324)]

Mr. A. Coward said:
Thanks for posting the "same news in norwegian". That is really "informative".Did you subscribe just so you could be the first to post some links just to get karma?

Hey coward, your post was really interesting. I don't really care about the karma, I mean what does it do for me? Currently, it is "good". It used to be "positive". I don't even know if I'm going up or down. :)

I'm a staffer on the norwegian site. I don't know how many norwegian readers Slashdot has, but seeing as norwegian

Article is in Sci-Am

[madaxe42 (690151)]

Very good article on this in scientific american, if anyone is interested!

Re:Article is in Sci-Am

[LucidBeast (601749)]

I assume that Sci-Am doesn't explain how Jesus was able to walk AND propel himself on water.

A related article (as seen on Fark)

[sczimme (603413)]

The Independent has a related article here [independent.co.uk].

Sculling...

[LouisvilleDebugger (414168)]

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?

Re:Sculling...

[radish (98371)]

There are quite a few little black boats in venice [drewnoakes.com] which use sculling to move along, so yes, I think it's safe to say it does work.

Re:Sculling...

[HiQ (159108)]

Yep I can, or at least could. When I was a kid I used to do this all the time in small rowing boats. And you don't actually make circular or elliptical movements, but something resembling an 'infinity' symbol (fgures eight). That is with your hands; the blade of the oar starts making an elliptical form through this, with the blade pressing against the water when you move 'along' the eight and slicing through the water when you turn the 'corners' of your figure eight.
Sorry for the rather vague description, b

--- uber sculler

[madaxe42 (690151)]

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 on

Duh...

[jeffkjo1 (663413)]

Everybody whose anybody knows waterstriders use anti-matter as propulsion.

A challenge

[D0wnsp0ut (321316)]

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.

Don't need to read it.

[rde (17364)]

a) It's in Christian Science Monitor
b) It's about skimming over the water.

Chances are, Jesus features in the answer.

Re:Don't need to read it.

[The Ape With No Name (213531)]

Ummm. CSM is about as good as a balanced source as you will find and, despite the name, they don't do ridiculous things like you are talking about. My local rag [knoxnews.com] will probably run this on the Religion section this week rather than the Science page. You should know better. Kind of like Brit "Goebbels" Hume, questioning the source of an eyewitness account of American soldiers abusing Iraqi citizens, by saying, "What do we know about this paper The Manchester Guardian?" rather than saying, "Secondary sources have yet to confirm or deny the report from the Guardian.

Asian Giant Water Strider

[Durendal (607361)]

A longer article [washingtonpost.com] 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..

[kmak (692406)]

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!

Amazing

[Vexalith (684137)]

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.

Re:Amazing

[Exiler (589908)]

To be honest, I am quite amazed that you believe humans as a species will survive a few thousand years... turn on the news, man =/

Do they have them everywhere

[Cackmobile (182667)]

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.

Re:Do they have them everywhere

[AndroidCat (229562)]

Of course they get everywhere. They have such nifty propulsion systems after all.

Re:Do they have them everywhere

[Jerf (17166)]

Water striders. [google.com]

Now that...

[Akardam (186995)]

... is a bug!

Re:Now that...

[borgboy (218060)]

Nope. It's a feature!

Re:Now that...

[danger42 (302987)]

No, it's Aragorn.

Surface tension is cool!

[PhysicsExpert (665793)]

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.

Matthew 14, 25

[godot42a (574354)]

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.

Re:Surface tension is cool! - Troll Alert!!!

[pdp11e (555723)]

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.

Impressionist Insects

[unfortunateson (527551)]

Go take a gander at the original BBC article [bbc.co.uk] 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.

Oh my...

[tkittel (619119)]

It seems that we have a Christian source of information related to walking on water?

At least it is their own IP :-)

Christian Science Monitor, eh?

[hankaholic (32239)]

Now: bugs walking on water.

Next up: evolution!

woo!

[Ninja Master Gara (602359)]

There's also a BBC story with pictures.

Ooooohh Pictures!

Dr. Bush

[fruity1983 (561851)]

"Doctor" and "Bush". After the last few years, I have a lot of trouble visualizing that...

Probably known about for a long time

[panurge (573432)]

In England water striders are known as water boatmen. Boatman=person operating small scull boat for short distance water transport. This suggests that the "sculling" action has been recognised for a long time.

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".

water boatmen != water strider

[Suchetha (609968)]

water boatmen [museums.org.za] are not water striders [ou.edu]

Suchetha

Re:BOOoooooring

[Cackmobile (182667)]

Well this is news for nerds and science is a pretty nerdy subject!

Re:Christian Science Monitor

[by Anonymous Coward]

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.

Re:Let the Christian trolls roll

[zero_offset (200586)]

So what you're saying is, you're a Christian troll?

Re:Let the Christian trolls roll

[by Anonymous Coward]

the microorganisms that live symbiotically inside of me think of me as "God".

Re:Let the Christian trolls roll

[d34thm0nk3y (653414)]

I would say that unlike parent post, the CSM is actually quite objective.

Re:Let the Christian trolls roll

[JonathanBoyd (644397)]

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.

Re:Really cool

[overunderunderdone (521462)]

Actually if you look at the guy's home page [mit.edu] 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 [mit.edu] and soap film [mit.edu]

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 doe

Re:Water Tension

[srw (38421)]

> Now all we need is to figure out how to make water have enough tension to hold a person. Hrmm...

Simple. This happens naturally where I live. I simply have to wait until, say, mid-November. The surface tension remains high until some time in spring. It only works for water kept outside or in an unheated building.

-srw