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Gil
November 17th, 2004, 05:26 PM
A bailisk lizard literally runs on the waters surface. How? "Its right leg sweeps back and inward in a movement that is very similar to the crawl stroke when swimming" . The result is an S-shaped movement as it thrusts forward. Comments?

newmastersswimmer
November 17th, 2004, 06:02 PM
Very Interesting....Where did you find this little tidbit by the way?.....Was it from the discovery channel or Science Magazine I wonder?......If we were to pull hard enough (and fast enough?) during freestyle, will the fuselage of our bodies then rise above the water so that we are actually just skimming the surface of the water?...I wonder???

newmastersswimmer

Seagurl51
November 17th, 2004, 08:41 PM
I have seen those lizards before on TV, very bizzare. Wouldn't that be fun to be able to do though. Get in perfect balance and then skim the top of the water rather than recover underneath. That would be cool to see swimmer do! Meets would get very interesting...who can get the most height, most distance!!

~Kyra

Brian Stack
November 17th, 2004, 09:32 PM
Originally posted by Gil
A bailisk lizard literally runs on the waters surface. How? "Its right leg sweeps back and inward in a movement that is very similar to the crawl stroke when swimming" . The result is an S-shaped movement as it thrusts forward. Comments?
What about the rest of it's legs???

Kevin in MD
November 18th, 2004, 02:23 PM
1. What a lizard does while running and what we do while swimming probably have very little to do with each other.

2. Since we have tossed aside the S pull as generating lift in a Bernoulli's law of fluid motions sense and the generating lift with shed vortices seems to be rather tenuous, what is going on?

2a. We got here by coaches coming to the conclusion that good swimmers use an s pull and then trying to make the physics fit the situation. Did the good swimmers actually use an S pull relative to the water or was it a misunderstanding of motion relative to the water vs motion relative to the body compounded by a lack of motion capture means at the time.

2b. Isn't it possible that any S shaped pull relative to the water exists for biomechanical reasons rather than those of lfuid mechanics?

2c. Unlike lizards, we have all been trained to swim in one way or another. Is there any way to do scientific studies that would negate our training.

Guvnah
November 18th, 2004, 03:54 PM
Originally posted by Brian Stack
What about the rest of it's legs???

I think these are the lizards that run on 2 legs when crossing water. The are pretty upright in posture. The rear legs are far larger than the forelegs. They just kind of hold their "arms" in a position that is not too different from what humans do.

And they have pretty large back feet.

The creatures weigh all of a few ounces. If humans were to do this, they would have to have tremendous leg strength and HUGE feet!

Gil
November 19th, 2004, 05:26 PM
Jim, Although I read Discover and Scientific American the article did not come from either. It was in our local paper. Sorry, I do not have the original source.

mattson
November 22nd, 2004, 12:37 PM
Originally posted by Guvnah
The creatures weigh all of a few ounces. If humans were to do this, they would have to have tremendous leg strength and HUGE feet!

Good point. There are spiders that can stand on the water, due to surface tension, but it'd be pretty hard for a human to do that.