• Photo: Bjørn Christian Tørrissen

What goes up doesn’t necessarily come down, especially when it’s a gecko. The tiny lizards can walk up walls and across ceilings because the minuscule hairs on their feet bind them to surfaces through Van der Waals force, the same force that holds water molecules together. Researchers such as Dan Sameoto, a professor of mechanical engineering at the University of Alberta, have long touted the gecko’s seemingly sticky grip as a key to developing new adhesive materials. Sameoto recently produced an adhesive that mimics the directional stickiness of a gecko’s foot.

What got you interested in geckos?

It was back in 2002, when the Van der Waals force was first discovered as the primary mechanism by which geckos adhered. The force had a lot of really interesting properties, including being able to work in extreme environmental conditions. The gecko, of course, can run around when it’s wet, dirty and dusty — conditions in which you’d never be able to get standard tape to work.

What are some of the applications of the new adhesive?

I could design shoes that have really high friction in one direction and that give me great stability, but aren’t tacky. Or an anti-slip shoe that sticks strongly to ice but doesn’t give you the feeling that you’re walking through bubble gum.

Do you have a new-found respect for these animals?

Yes. We can do a lot of things with our manufactured materials, but a gecko still out-performs us when it comes to climbing on natural surfaces and in extreme environmental conditions. If you examine their dexterity, they make it look so simple, but it’s really not. It takes a lot of engineering to even come close to the same functionality.

So it takes a lot of time to catch up with evolution?

Evolution has had millions of years on us, but I think we’ve done a great amount of replication in the last 10 or 15 years since the gecko adhesion techniques were first developed.

Do you have geckos in your lab?

I’ve wanted one as a pet for a while now, but my wife says no.