Over the past 16 years, scientists have studied geckos, lizards with nocturnal able to make sounds to communicate and to scale vertical surfaces thanks to adhesive pads placed on the soles of his feet. Although scientists have spent years studying these skills for application in nanotechnology and biomimicry, it is not known almost nothing about the origin of its adhesive capacity.
A team from the University of California, Riverside (EU), whose research focuses on dwarf geckos of the genus Gonatodes, has found some answers in the Gecko Trinidad (Gonatodes humeralis), found in South America and can climb surfaces as smooth like leaves and stalks of bamboo.
“Our analysis shows that this lizard has microscopic hairs, called setae, under your feet, which allows you to climb smooth surfaces without the complex structure that characterize the feet of geckos with which we are most familiar,” says Timothy Higham, Biology associate California university professor and author of the study published in Biological Journal of the Linnean Society.
The results demonstrate that the setae interact with surfaces via links ranging from Waals forces between molecules with (or between parts of the same molecule) than those due to an intramolecular link.
According to scientists, the hairs on the pads Gonatodes humeralis provide an advantage to climb all surfaces, even the most slippery, and avoid predators and occupy habitats where other geckos do not access the same gender.
Some atypical adhesives pelillos
The setae of this species are short and simple compared to the tokay gecko, for example. These are located next to small structures that increase friction calls spinules, which play no role in adhesion and found underfoot of many lizards. For authors, the setae of G. humeralis are the result of a transformation of spinules.
“So far we have not seen a gecko showing the beginnings of the adhesive system”, says the scientist who adds that “small changes can lead to complexity.”
The capabilities of this kind of geco offer an intermediate stage in the evolution of adhesion apparatus. The work indicates that the origin of this ability in the geckos has been gradual and has undergone significant changes in their ecology and function.
“The system is relatively simple adherence of G. humeralis indicates that slight changes in the shape can dramatically influence the functional outcomes and ecological niches that can be exploited,” says Higham. subtle morphological changes are able to trigger a radical change.
