Though they are marvels of God’s design, that probably isn’t your first thought when you suddenly notice one dangling from the ceiling only a few inches from your face.
Beware: We’re about to talk about spiders.
While they tend to give people the “creepy crawlies,” spiders really do reveal the magnificence of their Designer’s intelligence and engineering skills. And that thread from which they dangle—a silken fiber that seems almost impossibly thin—is one of the most remarkable materials in the natural world, earning intense scientific interest and the attention of researchers hoping to duplicate God’s handiwork.
Let’s allow ourselves, just for a moment, to become wrapped up in the spider’s web and see what we can learn of its Creator.
USED IN MANY WAYS
When visualizing a spider’s web, it is easy to think only of the beautiful and seemingly delicate cobwebs we commonly notice. But, as we’ll see, spiders create a silk that is a virtual "miracle material" capable of many uses, and the world’s spiders use it in an astonishing variety of ways.
For instance, some spiders in the Cyclosa family use debris in their webs to create crude spider-shaped decoys, larger than themselves—then shake the web to make the spider facsimile seem all the more like a larger and more dangerous threat to potential predators.
Bolas spiders get their name from weighted and roped weapons, thrown by South American gauchos, which capture animals by tangling their feet—an association that becomes clear when you watch these spiders in action. Hanging under a leaf or twig, the bolas spider will dangle from one of its legs a single silken thread, weighted at its end by a drop of specialized sticky fluid. Upon the approach of a moth, the spider will swing its thread like a lasso, hoping to latch the sticky droplet onto the moth. Once captured, the spider reels in its prey and dinnertime commences.
Even more ordinary webs may surprise us with the inventive ways in which spiders apply them. For instance, the “triangle weaver” spider has a remarkable way of taking full advantage of its web’s remarkable elasticity and tensile strength. The spider anchors itself on, say, a nearby twig, then pulls its webbed net back tightly—the way a human archer would pull back the string of a bow to launch an arrow. Once prey is within the spider’s range, it lets go of its anchor, shooting both spider and web toward the doomed insect.
There are so many ways in which different species use their webs. Spiders deploy their unique webs to build trap doors, create funnels that signal when prey has arrived, bind leaves together to create a hideaway home, craft a net they can grasp with the tips of their legs to snare their victims unawares, or even perform “ballooning”—a means of locomotion in which some spiders use threads of their webbing to take advantage of gentle wind currents and atmospheric electricity to “fly” for hundreds of miles. It seems that with every species of spider comes another application of spiderweb.
A MATERIAL LIKE NO OTHER
None of these amazing and creative accomplishments would be achieved were it not for the ingenious materials made possible by the spider’s versatile silk. While the thin threads of a spider’s web may seem fragile and flimsy, they are quite the opposite. Spider silk is the toughest fiber scientists have found in nature—lighter than cotton, yet stronger than steel. The Darwin’s bark spider, which creates the strongest silk ever discovered, produces strands with ten times the strength of Kevlar. Scientists are still plumbing spider silk’s properties and studying its design, hoping to learn how to create new materials and technologies to benefit human life.
The spider’s silk starts out as a liquid in an abdominal gland. Spiders actually have multiple glands, each responsible for creating a different kind of silk designed for a different range of purposes. For instance, an orb-weaver spider—creator of the spoked, spiraled kind of web we often see in our gardens—uses multiple silks depending on the task at hand. One kind of silk creates the temporary scaffolding of its web, while another, stronger silk creates the web’s spokes and outer supports. “Rungs” between the spokes are made with another more elastic kind of silk, resulting in threads that can stretch to more than twice their length without breaking. Another silk is used for creating egg sacs, and yet another to wrap its captured prey. Each task requires a different mixture of strength and flexibility, and a different kind of silk specifically engineered to best complement the spider’s goal.
Each variety of silk is created when liquid is pressed through valves and spigots that arrange protein molecules into solid strands before leaving the spider’s body. These microscopic spigots sit on the ends of small, finger-like organs, called spinnerets, protruding from the end of the spider’s abdomen. These spinnerets expertly wind the strands together to create the silk threads we associate with spider webs.
By varying multiple elements—say, the thickness of the threads that come out of the spigots, the combinations of the silk types that are woven by the spinnerets, or the specific manner in which the strands are combined—the fibers of the spider’s web can be assembled in a remarkable variety, each designed to serve a different purpose.
Of course, the current big-screen incarnation of comic-book hero Spider-Man has teenaged Peter Parker manufacturing “web shooters” he can use to produce webs at whim. But in the real world, scientists aren’t quite as successful as young Mr. Parker.
Not that they aren’t motivated! Spider silk has an impressive array of uses for humans, but such webs are not easily manufactured. So far, mankind has generally been able to do so only by borrowing the spider’s own secrets. Silkworms and bacteria—and, perhaps surprisingly, even goats—have been genetically engineered to produce spider-silk proteins for human manufacturing purposes. But the effort is expensive and produces only small quantities—not nearly the levels of production needed to power wind turbines or tailor mass-produced clothing.
Still, the potential is huge, and researchers continue to pursue this wonder material. The medical industry in particular is intrigued by the fact that spider-silk is biodegradable and does not provoke an immune or allergic response in humans. The prospects of regenerating ligaments and creating better skin grafts for burn victims have doctors intrigued.
But for all our best human efforts, we still cannot produce in mass quantities what a single spider generates effortlessly on a daily basis. The spider occupying a quiet corner of your home is, in a real sense, a materials engineer beyond compare.
So, the next time a spider startles you—and after you’ve had a moment to catch your breath—you might step back and appreciate what that spider represents: a testament to an ingenious Creator who gives to even the smallest of His creations some abilities mankind cannot yet achieve, asking us to examine the works of His hands and to see His greatness, ingenuity, goodness, and providence.