From making parachutes to building scuba tanks, the arachnids have come up with some fascinating creations
Spider silk is a wonder material that, weight for weight, is stronger than steel, tougher than Kevlar and can be more elastic than rubber. It’s also flexible and antimicrobial. Scientists have used silk to make bulletproof armor, violin strings, medical bandages, optical fiber cables and even extravagant clothing.
“I don’t think people would believe you if you told them, there’s this creature that, if you scaled it up … to the size of the human, it could catch an aeroplane with the material that it makes itself out of itself,” says Fritz Vollrath, an evolutionary biologist at the University of Oxford.
As Cords and Nets to Actively Snare Prey
Silk as a passive web for bugs to fly into may be the least interesting spider hunting method of all. To catch their next meal, spiders may use their silk as nets—or as lassos, whips, binds, disguises, fishing lines and lures.
Most spiders avoid ants because they are often predatory themselves, but one family of spiders treats ants as chow. When the wall spider (Oecobius) gets an ant alone, it runs circles around its victim, all the while churning out a silk cord and wrapping the ant from a safe distance. After the ant is all trundled up, the spider goes in for the kill by chomping the ant at the base of the antennae.
In 1883, the Krakatoa volcano in present-day Indonesia erupted with the force of over 10,000 hydrogen bombs, obliterating most of the island and converting it into a lifeless wasteland. Three months later, visiting scientists were surprised to find one lifeform present in the region: microscopic spiders.
These spiders weren’t on the newborn island because they survived the blast. Rather, they had travelled there in the aftermath of the eruption—by ballooning. Now a well-known phenomenon, ballooning occurs when spiders stream their silk into the air, catching the winds like a sail for loft. Spiders have been found in the middle of the ocean, hitching a ride on the jet stream and on remote islands hundreds of miles from the mainland. Not all spiders balloon to travel extreme distances—some rely on it to flee from predators or cover short lengths without expending much energy.
As Home Décor
Orb-weaving spiders don’t just construct their homes from silk. Some of these spiders make an effort to decorate it too. They weave throughout their webs stripes of thickly banded silk called stabilimenta. Scientists first though these structures worked to stabilize the web, but the theory was disproved after they found that the patterns were only loosely knitted intro the web’s fabric. Today, the function of stabilimenta is still a mystery.
As Protection from the Elements
Jumping spiders roam freely during the day, but at night or in the midst of cold or rain, they will spin themselves a silken shelter. Jumping spiders use these “pup tents” to shed their external shell safely, store their egg sacs or hibernate. One scientist has speculated that the ability to spin cozy cocoons that insulate the spider from the cold is one reason the Himalayan jumping spider (Euophrys omnisuperstes) can survive the frigid temperatures at elevations of 22,000 feet, making it one of the highest-dwelling, non-migratory animals in the world.
As Buffers Against Tides
One spider spins cocoons to protect itself from the daily tides where it dwells. The Desis spiders scuttle amidst coral, abandoned seashells and the bottoms of kelp on the beach during low tides. When the water rises, the spiders seal themselves in these nooks and crannies with waterproof silk. Researchers have found that the spider lowers its breathing to reduce how fast it burns through the oxygen in its air pocket. Scientists still have questions—such as how the web can withstand salt or how the spider keeps time with the tide.