Spider Sense
An Animal Rights Article from All-Creatures.org

FROM

John Thompson, Animals and Society Institute (ASI)
January 2013

He makes his own parachute and jumps from the highest places. She invests hours in spinning a web then eats it all when she wants a new one. They can spend an entire day hanging upside down. They are patient beyond description, waiting, waiting, waiting for someone to fall into their beautifully crafted trap.

Spiders quietly go about their business, usually entirely unseen by us. But some scientists have built careers on studying the marvelous lessons a spider has to teach. Take the miracle of the web.

The strands of some spider webs are stronger than steel. And they are highly flexible and stretchable. If a black widow spider were to weave a bullet proof vest it would be infinitely lighter and offer more protection than traditional Kevlar vests. With that material you could build incredibly light airplanes and automobiles that are stronger and much more fuel efficient. Suspension bridges wouldn't need high maintenance metal cables, just wrapped strands of web material. And spider silk conducts heat as well as, or better, than many metals.

Considering the strength of spider silk, one scientist did the math and asserts that a single strand the thickness of a pencil could halt a Boeing 747 airplane in flight. There are no plans to test that theory.

Typical orbed spider webs like those we find in our gardens are made from at least two kinds of silk. The dragline strands that run straight from the center to the outer perimeter are rather stiff, hard and dry. They provide structural support for the web. Viscid silk, the strands that form concentric circles, are wet and very sticky. They attach to the draglines. Insects become glued to the viscid silk and the vibrations from their struggling alerts the patiently waiting spider.

Why don't spiders become entrapped in the stickiness of their own webs? The spider's brain performs the intricate calculations that keep all eight legs on the dry dragline strands even when running at top speed. An amazing mental feat! And a slightly non-stick coating on the legs helps with occasional passing brushes. Some species also keep a strand of silk attached to their body as a safety line in case they fall off.

Even though its elasticity allows a typical web to withstand high winds it can be damaged. The web's ingenious design, though, keeps damage localized so that the entire web isn't a loss. And when it is time to build a new web many spiders recycle the protein by eating the old one.

Given the current attitude toward using other species you might ask why there aren't factory spider farms to harvest the amazing silk. The species that produce the best silk, though, are spared that fate because they are too territorial and aggressive for concentration camp living. But scientists are finally learning how a spider aligns the protein and nanoscale crystals in its silk to create such impressive strength. This is one example of the relatively new science of biomimicry, profiting from paying attention to the natural world rather than just destroying it.

Spiders exhibit intelligence, resourcefulness, and the ability to learn. Some, like the Portia genus, study specific behavior patterns of other spiders they would like to have for dinner. Then they create unique attack strategies using that knowledge. That is brain power!

By most modern standards spiders deserve the title of "sentient." And they deserve our respect and our appreciation for the important work they do in maintaining a balance of life in their ecosystem.

Rather than squashing the next spider we encounter, or tearing down its finely spun web, let's just pause and appreciate the miracle and beauty of our eight-legged brethren. Their lives are truly interwoven with ours.

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