Running on water added to gecko's impressive list of capabilities
The superhero-like abilities of the humble gecko have inspired countless avenues of scientific research, and biologists have uncovered yet another incredible talent to add to the list. The researchers have found that the enterprising lizard species also has the ability to run on water, a capability that could lead to the development of advanced robots that do the same thing.
Whether its advanced adhesives modeled on their sticky feet, new materials that follow their example of cleanliness, or spinal cord treatments inspired by how fast they can regrow their discarded tails, the gecko is rich source of stimulation for scientists from a variety of fields.
The latest-gecko inspired research stems from observations both in the wild and in the lab that the creature is able to skitter across puddles to evade predators. Scientists at the University of California, Berkeley, together with study co-authors from the University of Oxford and Rockefeller University, set out to investigate this further by using high-speed video to reveal some of the mechanics at play.
By building a long water tank, placing geckos on a plank at one end and touching their tails, the scientists were able to spur the creatures into action. The high-speed video provided them with a means to closely study the techniques the animals use to stop themselves from sinking, and also estimate some of the forces involved.
Their conclusions describe a creature that combines special capabilities from all corners of the animal kingdom. Like small insects such as spiders or water striders, geckos rely on surface tension to stay on top of the water, but that's only part of the picture.
Because they are much larger than those creatures, they weigh too much to rely on surface tension alone. So they combine this with a slapping action that produces enough force to help keep their heads above water, similar to that used by a swan when taking off from the surface. At the same time, its smooth water-repelling skin helps it plane across the surface like a muskrat, while its tail swishes through the water like an alligator, providing propulsion, lift and stabilization.
"All are important to some extent, and geckos are unique in combining all these," says Robert Full, a UC Berkeley professor of integrative biology.
The team found that the geckos were able to run on water at a rate of nearly one meter (3 ft) a second. They are yet to confirm if the creature can turn that water into wine, but the unique set of techniques it uses to stay afloat could lead to new, more effective aquatic robots. One example the study authors point to is the concept of a bipedal water-running robot inspired by basilisk lizards. Adding the planing abilities of the smooth-bellied gecko and an undulating tail to the mix could improve their energy efficiency, velocity and stability.
To see the geckos run on water in the lab at UC Berkeley, check out the video below.
Source: UC Berkeley