Reptile & Amphibian Forums

I plan on doing a "reptile show" for the kids in my son's homeschool group, and I wanted to give them some information on how EXACTLY a gecko sticks to walls and etc...is there a website, or can someone explain this in understandable language? Thanks. Also, if anyone has some interesting info about geckos, that would be great.

Marcy

There is a very weak attraction between molecules called the VanderWaals force. Anytime you get molecules near each other, this force makes them attract to each other, but very very weakly. However, geckos have microscopic folds on their feet from which grow millions of microscopic 'hairs' called lamellae. These folds and hairs give the gecko's feet a lot of surface area, which means that a LOT of molecules on their feet come in contact with the surface that they're standing on. The feet have so much surface area that this weak molecular force becomes strong enough to support their body weight.

I'm sure someone else will have a website that's better. If it helps, fly's feet stick in the same way.

Like stated the Lamallae are microscopic hairs and each toe has millions of them. I like to think of it like this. You know how the moon looks smooth to the eye in the sky but when viewed with a high powered microscope it is full of large craters. Every known surface like marbles and glass is the same way and these micro scopic hairs are able to find and fill every nook and crack that is unseen to the eye given the gecko a very powerful hold. If you watch a gecko move they actually curl their toes up to release the hold.Hope that helps its my easy explanation when I'm asked.
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My posts and replies are my experiences only
1.2.6 Tokays
1.4.6 Leos(9 albino)
0.2.0 AFT's
0.2.0 Stenodactylus Petrii(Dune Geckos)

Thats too easy. They do not mechanical grap into tiny crevices and the like.
They much more bring the spatula like tips of their lamellae "hairs" in such close proximity to the surface atoms of the substrate that interatomic forces begint to matter.
These minute Van der Waals forces sum up to a force which can hold the gecko- and much more weigth...

Ci@o

Ingo

Tell them it works like velcro. Just very very small velcro thats all. No need to explain Van Halen to them its not in their time

But i does not work like velcro. Not at all. So why say that?

Look at the link below-its free.

And if you have access, check these:

1. Adhesive force of a single gecko foot-hair

Kellar Autumn, Yiching A. Liang, S. Tonia Hsieh, Wolfgang Zesch, Wai Pang Chan, Thomas W. Kenny, Ronald Fearing, Robert J. Full
SUMMARY: Geckos are exceptional in their ability to climb rapidly up smooth vertical surfaces. Microscopy has shown that a gecko's foot has nearly five hundred...
CONTEXT: The foot of a Tokay gecko (Gekko gecko) has about 5,000 setae mm-2 (ref. 4) and can produce 10 N of adhesive force with approximately 100 mm2 of pad area (Fig. 1a-d). Therefore, each seta should produce an average force of 20 µN and an......
Nature405, 681 - 685 (08 Jun 2000) Letters to Nature
Abstract | Full Text | PDF
2. What's blue and sticky?

Description: The toes of the Tokay gecko, shown above, are worth a closer look because......
CONTEXT: The toes of the Tokay gecko, shown above, are worth a closer look because they can adhere to the smoothest surfaces. But this isn't the only neat feat that reptiles can perform. It is well known that chameleons can change colour for......
Nature421, 479 (30 Jan 2003) Book Reviews
Full Text | PDF
3. The patter of sticky feet

Description: Nature Science Update: The latest science research and news reported by......
CONTEXT: ...A Tokay gecko clings to a piece of polished glass. Inset images show the underside of the foot and an electron micrograph of the minute spatulae at the end of each foot hair. Image © Robert Full Geckos scamper across the......
http://www.nature.com/nsu/000608/000608-11.html
4. Biomechanics: Gripping feat

Henry Gee
SUMMARY: The adhesive properties of the feet of geckos are remarkable, enabling them to scuttle up walls and across ceilings. From force measurements on the hairs...
CONTEXT: ...681-685; 2000), Autumn et al. come the closest yet. Their force measurements on adhesive setae (foot-hairs) from the Tokay gecko, Gekko gecko, are consistent with the rapid formation and breaking of intermolecular bonds -- van der......
Nature405, 631 (08 Jun 2000) News and Views
Full Text | PDF
5. Gecko glue round the corner: Geckos' hairy grip inspires adhesive research.

SUMMARY: Geckos' hairy grip inspires adhesive research....
CONTEXT: ...The soles of Tokay geckos (Gekko gecko) have sticky ridges called lamellae. The ridges of each foot contain half a million hairs, called setae. The end of each hair splits into between 100 and 1,000 tiny spatulas, visible only with......
(28 Aug 2002)
http://www.nature.com/nsu/020826/020826-2.html
Paper on the topic

The geckos that can climb up smooth surfaces and accross cielings can do so, because the underside of their feet are covered with microscopic hair like structures called lamalae. These lamalae are covered in spatulae and the spatulae are covered in setae. There are billions of setae on the geckos feet. Because these structures are so small they fit between the molecules on the surface of what ever they come in contact with. An intermolecular force is created which is so strong it holds the gecko on with ease. The gecko can hold its weight with one toe! Effectively, it is as if the gecko is part of the object that it is on (ie. if the gecko was on a wall, it is as if the gecko is part of the wall).
You may now be thinking, well how does the gecko move? will it not be stuck down in one place forever? Well the answer to this is that the gecko curls its toes to reach an angle of 45 degrees from the surface. At 45 degrees the intermolecular force is overcome and too weak, therefore the gecko can move at rapidly in this way.
P.S. many anole species have this same ability too.

I know all the new research that is available but for a long time nobody knew how and my explanation is one that I read about and is basically the same in very easy to understand laungage for children to comprehend, if their not old enough to understand more scientific language. I thought it was very simple and easy like she asked for. And by the way I enjoyed the responses, it is very facinating how they do it. I've read NASA is experimenting with gloves that do the same thing.
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My posts and replies are my experiences only
1.2.6 Tokays
1.4.6 Leos(9 albino)
0.2.0 AFT's
0.2.0 Stenodactylus Petrii(Dune Geckos)