Scientists have created artificial spider webs to try to uncover their mysterious properties. They wanted to understand why spider webs always stay taut even when people played around with them.
In an article published in scientific journal PNAS, the researchers from the University of Oxford and the Université Pierre et Marie Curie in France have examined spider webs' impressive resistance and elasticity. They noted how they never appeared to sag, even after being stretched many times their original length.
In their research, they show that this phenomenon is made possible by the tiny droplets of watery glue coating the web's fibres. If there is any loose thread, it is instantly spooled inside these droplets.
"The thousands of tiny droplets of glue that cover the capture spiral of the spider's orb web do much more than make the silk sticky and catch the fly. [...] It is used to excellent effect to keep the threads tight at all times, as we can all observe and test in the webs in our gardens," explains Prof Fritz Vollrath of the Department of Zoology at Oxford University.
This discovery has inspired the team of scientists who have since then created composite fibres in their lab based on a novel liquid wire substance and similar to the arachnids' webs. The artificial threads are able to extend like a solid and compress like a liquid. Just like spiders' capture silk, they rely on a subtle balance between fibre elasticity and droplet surface tension.
The discovery is interesting for biologists who study spiders and how they interact with their environment, but the novel artificial webs may also be a stepping stone in creating new bio-technologies. Such a resistant and elastic material could indeed be put to good use in diverse fields, from medicine to engineering.
"Spider silk has been known to be an extraordinary material for around 40 years, but it continues to amaze us. While the web is simply a hi-tech trap from the spider's point of view, its properties have a huge amount to offer the worlds of materials, engineering and medicine," says first author Dr Hervé Elettro, from Université Pierre et Marie Curie.
"Our bio-inspired hybrid threads could be manufactured from virtually any components. These new insights could lead to a wide range of applications, such as microfabrication of complex structures, reversible micro-motors, or self-tensioned stretchable systems."