Gecko climbing glass

Geckos are lizards renowned for their remarkable ability to climb smooth surfaces like glass, thanks to adhesive lamellae on their feet.

About this subject

Geckos are one of the most diverse lizard lineages, with over 1,500 species found on every continent except Antarctica. Primarily nocturnal and arboreal, these reptiles are especially abundant in tropical and subtropical regions. Many species, such as the common house gecko (Hemidactylus frenatus), have adapted to urban environments and are frequently seen on walls and ceilings.

The ability to climb glass and other smooth surfaces lies in microscopic structures on their feet called lamellae, covered by millions of even smaller hairs, the setae. These setae generate van der Waals forces, an intermolecular attraction that allows the gecko to adhere firmly without using fluids or suction. It is estimated that a single gecko can support up to 200 times its own body weight with this adhesion.

Ecologically, geckos are important controllers of insect populations, such as mosquitoes and cockroaches. Some species are kept as low-maintenance pets, such as the leopard gecko (Eublepharis macularius). Engineering inspired by gecko adhesion has already led to the development of reusable adhesive tapes and climbing robots.

Interestingly, many geckos have the ability to autotomize, detaching their tail when threatened by predators. Some species emit vocalizations, like the chirping of the house gecko. Their night vision is exceptional, with vertical pupils that regulate light intake. These lizards have evolved to maximize the use of vertical and moonlit niches.

Frequently Asked Questions

How do geckos manage to walk on glass?

Geckos use millions of microscopic hairs called setae on their feet. These setae generate van der Waals forces, an intermolecular attraction, enabling adhesion to glass without suction cups or sticky substances.

Do all geckos climb glass?

Most gecko species have this ability, but it varies by species and surface. Geckos with well-developed lamellae, such as those in the subfamily Gekkoninae, are especially adept. Some, like the leopard gecko, have claws instead of adhesive pads.

Are geckos dangerous to humans?

No. The vast majority of geckos are harmless and beneficial, as they feed on insects. They are not venomous and rarely bite. In domestic settings, they help control pests like mosquitoes and cockroaches.