Talk:Animal locomotion on the water surface

(Something showing an animal in motion would be good, e.g. a lizard) Richard001 05:01, 28 August 2007 (UTC)

Original research
Firstly the article needs to establish that it is not original research. Then, some questions (and remember I know only what I've read here):


 * The "vertical force" from the surface layer is presumably counteracting the weight i.e. acting vertically upwards, right? Or have I missed something? answered
 * What is a "contact perimeter"?
 * There is an implicit statement that this page is only upon creatures where mg/(σP) < 1. Is this true? If so, need to be explicit. answered Sliggy
 * Does the next paragraph repeat itself over the two sentences? Is there a word missing?
 * The fact about the Gigantametro Gigas is interesting, but could we have some other data points for comparison? Otherwise it's just a random number. Whoo-hoo, but meaningless. Also, any reason why their legs get longer as they get bigger?
 * The description of thrust generation sounds more like a mass transferrence (grab a bucket of water and chuck it backwards). Maybe a diagram might help? Or a re-write (eg filaments of what? Hair?)
 * The water deformation via body posture definitely needs a diagram. I can picture the meniscus, but not how the heck it is deformed to surf on to dry land.
 * I don't really see a solution to Denny's paradox in this article, or is it because I am ignorant of the subject and simply didn't notice it? It's in water strider. Doh. Sliggy

Just some random questions. Sliggy 22:59, 4 January 2006 (UTC)

AfD
This article survived an AfD. The discussion is here. enochlau (talk) 23:22, 10 January 2006 (UTC)

trimmed verbiage
(in m g (where m equals the mass of the animal and g the gravitational acceleration) &sigma;P (where &sigma; equals the surface tension and P equals the contact perimeter of the animal's feet).

Broader article?
How about something like life on the surface of water. This could summarize this more specific article. Richard001 (talk) 08:16, 6 February 2008 (UTC)

Non-existant See Also?
The article link to Robostrider under "See Also" is non-existant, should this be? Okiesmokie (talk) 09:21, 13 August 2008 (UTC)

Liquid Mountaineering
Allegedly "liquid mountaineering" is a method for "walking on water" that could be employed by humans. And, allegedly, it works, as seen in |this video on YouTube. —Preceding unsigned comment added by U-D13 (talk • contribs) 10:04, 12 May 2010 (UTC)


 * It's fake - completely impossible. Youtube is teeming with fake videos, including this one, and therefore is not a reliable source. Mokele (talk) 12:09, 12 May 2010 (UTC)


 * So, I suppose you have done a really thorough research on these "liquid mountaineering" claims? Could you please be so kind, and share with the community all the indisputable evidence you have gathered that confutes this "liquid mountaineering" as totally physically impossible? Nameless Undead (talk) 21:02, 18 May 2010 (UTC)


 * I don't have to present squat - they/you are the ones making the claim, and for such an extraordinary claim, they/you need something more convincing than a crappy youtube video that I could replicate in 5 minutes with a camcorders and a plank of wood held 3 inches below the water surface. This isn't even Special Effects 101 - kids can figure out to fake a shot like that.
 * However, the rationale for skepticism is pretty obvious - every animal which is capable of locomotion on the water's surface is either *extremely* light (various small arthropods) or possesses tremendous foot surface area (as in the basilisk lizard) because they must maintain upward thrust by displacing a give volume of water at a given speed. Basilisk lizards are right on the edge of what's possible - similar lizards that are larger/bulkier/shorter-toed fail to move across the surface, as do basilisks themselves if their speed drops below near-maximal.  So given that we have 500x the mass, but only ~5 times the foot area and slower muscles (therefore slower foot extension), it's impossible.
 * Seriously, we actually have a better shot at flying by attaching fake wings to our arms and flapping really hard - at least in that case, organisms of our mass have done it before (teratorns, azdarchid pterosaurs) and we only fall short by about 5-10-fold, rather than by 100-fold or more.
 * But all of that is irrelevant - it is up to you to provide evidence for this claimed phenomenon. Mokele (talk) 00:12, 19 May 2010 (UTC)


 * Okay, this puts an end to the discussion. I'm really ashamed for falling for it and sorry for wasting your time. Nameless Undead (talk) 10:23, 23 June 2010 (UTC)