‘Yikes!’ is a typical response to the spider, never mind its celebration in prose, verse and movies. Unlike popular perception, most of these eight-legged ‘monsters’ that trigger arachnophobia in people don’t even have jaws strong enough to pierce your skin. Of the ones that do, only a very few actually have harmful venom (and even this can be used to treat sick people!) The world’s biggest spider — the hairy tarantula that could easily cover a large dinner plate — is a shy creature that hides in burrows and hardly ever bites. So the more we know about spiders, the less startling — and more amazing — they seem.
Around even before the dinosaurs, and with over 36,000 different species documented on every continent except Antarctica, spiders keep other pesky insects under control. Minute hair, or setules, on the spider’s feet, for instance, generate enough electricity to support an astonishing 175 times the creature’s weight, enabling it to defy gravity, and cling, clamber and swing. If technology can replicate this, it’ll open up exciting possibilities for future astronauts to attach themselves to their spacecraft in zero gravity.
Spider experts David Penney of the University of Manchester and Vicente Ortuno of the University of Alcala, Spain, recently discovered the world’s oldest arachnid: a 120-million-year-old fossil, preserved in an ancient chunk of amber in a Spanish museum. The find, described in Science, confirms the wheel-shaped web as the earliest structure used by spiders to capture prey.
A spider’s web is spun with its ‘silk’, a protein whose molecules create intricate bonds with neighbouring molecules. When spiders secrete this protein, it hardens and pulls taut, crystallising into a strong cable able to withstand the impact of a hurtling fly. Eight times stronger than steel fibre of equal diameter and incredibly ‘stretchy’, it’s tougher than Kevlar but weighs only a third as much.
{{/usCountry}}A spider’s web is spun with its ‘silk’, a protein whose molecules create intricate bonds with neighbouring molecules. When spiders secrete this protein, it hardens and pulls taut, crystallising into a strong cable able to withstand the impact of a hurtling fly. Eight times stronger than steel fibre of equal diameter and incredibly ‘stretchy’, it’s tougher than Kevlar but weighs only a third as much.
{{/usCountry}}This makes it ideal for applications like extremely thin sutures in eye or neuro-surgery, artificial ligaments and tendons, bulletproof vests, and fishing nets. So unique is the web’s geometry — balancing stresses and tensions, and distributing forces across its surface — that, taken on a human scale, it could catch a jetliner!
It also holds valuable lessons for engineers who build tent-like structures with many cables. But attempts to make spider silk synthetically pale before nature’s undisputed high-performance polymer fibre, fine-tuned by millions of years of evolution.
Once the genetic coding for spider silk is sequenced, researchers will be able to unravel
its molecular architecture and spin some remarkable scientific yarn of their own.