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Scientists Discover What Makes Geckos Stick
Scratch-O-Matic writes "This story at CNN explains how gecko feet are sticky due to an electro-mechanical phenomenon rather than a chemical glue, as had been previously assumed. The gecko is one of just a few animals capable of climbing vertical and beyond-vertical surfaces that are smooth and dry. Researchers have discovered that the secret to the adhesion lies in millions of tiny hairs called
'setae.' Each hair is the width of two human hairs, and contains about 1000 little pads at the end. The pads are so tiny that they actually cling to the surface at the molecular level, due to van der Waal forces. A gecko using all of its setae and pads at the same time could support 280 pounds. Seems to me that his should be easily replicated in the coming age of nanotechnology." Other readers point to the AP story, as carried by Yahoo! and also playing at Salon.
Cool, maybe now I'll get to climb walls like Spiderman. Afterall, what's a better use for new technology than for recreation.
Truthfully though, this could be useful in a lot of applications. I would expect to see NASA interested, as it might be a good replacement for velcro, which is kinda limited in what it can stick to.
Necessity is the mother of invention.
Laziness is the father.
I just love my Tokay Gecko. It's as mean as it can be. The Tokay is the pit-bull of geckos.
I had a bad roach problem. I did'nt want to use pesticides in my home so a friend recommended a Tokay. I was open to all options so I bought a Tokay and let it loose in my home.
The roaches were gone in two days. It was lovely. I would wake up at night turn the lights on and see my little guy on a wall somewhere.
It did such a good job eating roaches that it eventually ran out of food. I had to catch it (not easy since it put up a good fight) and put in a terrarium where it happily eats crickets.
I love my little guy.
Here is a picture I took of my little buddy.
I was wondering the same thing, actually. Anybody here got any idea?
File under 'M' for 'Manic ranting'
If memory serves it's van der Waals.
It's an ultra-short range stickiness that applies to just about any material.
Anybody with a physics degree will be horrified by this explanation, but conceptually imagine two neutral atoms, really close. Imagine that atom A momentarily has more of its electron cloud on the side away from atom B. Then atom A will look slightly positive to atom B. A positive charge attracts electrons, so atom B's electron cloud gets redistributed toward atom A. Atom B now looks slightly negative, keeping A's electrons (better, A's electron probability distribution (better yet, we should be talking complex amplitudes and energy values)) on the far side from B.
Corrections and clarifications to the above are entirely welcome.
* Hands with non-slip grip. (To add this feature to your future child, select option 567B on the manipulators submenu. Special price of $433.34 for the next 10 minutes.)
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* Fasteners on living, plant-based clothing. (Anyone remember the ads for the "Playtex Living Bra?" This one has a clasp the most determined teenage boy can't pry off!)
* Biologically based near-future equivalent of a Velcro Wall. You don't need a suit . .
* Security floors. Intruders walk on but they can't walk off!
I wonder if there's some way of applying a low-voltage charge that would lay the hairs flat, and release the grip.
Imagine, if you will, a practical spidey-suit (hinted at in the CNN article). How would anyone with gloves like these be able to throw anything (like a pistol, say) out of his or her grasp?
I mean, I'm just thinking here; not really interested in becoming a superhero or nothin'. Really. Nothing to see here. Move along. *koff*
Agreed... I live in Costa Rica.. and the Geckos are there every night when I come home, just hanging out on or near the ceiling.
I figure they can hang out all they want.. they eat bugs, and they don't get into the food.
Besides, they are almost impossible to catch.
Some nights the outside of my house is almost swarming with them (okay exaggeration, but if I take a walk with the flashlight, I can usually find at least 10 on the outside of the house without trying)
Now.. if I can just figure out what that weird lizard that lives in the tree is..
that it has millions of hairs does not mean it has to let go all of them at at time.
so my theory is it lets go hair by hair, in fast order -- like it automaticly does when it walks.
if you take two-sided sticky tape and tape it to your soles it would be harder to lift your foot straight up than to just walk, wouldn't it?
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making up good sigs is a hard thing to do.
Apparently the story is better the second time around.
If the forces in use are only Van der Waals, and these forces are present everywhere, what makes geckos, or rather their little hairs, special so that their molecules can stick to walls and mine can't?
:).
If I understand correctly, it's because the hairs and pads are arranged so that the sticky pads can follow surface curvature down to a near-molecular level.
Most surfaces, even ones that are polished smooth, are very rough on a small scale. This roughness is actually fractal; it's not just one level of coarseness (like sandpaper), it's coarseness on many scales. Match it on one scale, and the next step finer still keeps most of the surface away from you.
So, if you put your finger on a surface, you're still not touching much of the surface, even if you press quite hard. This limits the amount of van der Waals adhesion you can get (as the effect happens over molecular distances).
A thin film of water or oil can fill the crevases and make the bonding much stronger, if you want to try sticking your fingers to things. Don't try hanging off the ceiling, though
Disclaimer: This explanation could be completely wrong. It's just the most plausible one I can think of.
Same thing with superglue. Glue your fingers together and try pulling them apart, incredibly hard to impossible. Ah, but rub your fingers like you're trying to light them on fire by friction, and voila! Something about the "shear" strength of the bonding.
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== WolfriderV6 == I'm willing to admit that *I just might* be wrong... Are you??