Not only van der Waals Forces, but Electrostatic Forces also Play Role in Adhesive Abilities of Geckos

Not only van der Waals Forces, but Electrostatic Forces also Play Role in Adhesi

A new paper has a different reason explaining what makes geckos walk smoothly on vertical surfaces. The study claims it is the static electricity that prevents geckos from falling.

Previous researchers claim it is van der Waals forces that geckos create and therefore, climb up walls with ease. The van der Waals force is created by intermolecular attractions by tiny hair present on gecko's feet and the surface on which it walks.

Researchers carried out experiments in which different surfaces were taken and electrical charge of gecko's footpad was measured. After those calculations, researchers found though van der Waals forces do play a role, static electricity is equally involved.

Researchers from the University of Waterloo in Canada explained climbing ability of geckos come from their specially adapted toe pads. Each of the pads has layers of microscopic, hair-like structures, which get split in to spatula-shaped tips.

Being so small, the tips get so close to the surface on which the geckos walk that a strong contact is formed. Together, the structure produces a combined adhesive force of about 10 N for each foot. It allows geckos to hang from a ceiling.

"This is a novel and important discovery, and suggests that electrostatic forces could contribute to adhesion in geckos on some surfaces, such as Teflon", said Kellar Autumn of Lewis & Clark College in Oregon, who was the first one to observe the Van der Waals force usage in gecko feet.

It is considered that the latest findings can overturn 80 years of conventional ideology that electrostatic interactions do not play role in gecko adhesion.

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