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Mexican redknee tarantula

Out in a Madbury, N.H., field one summer morning, Tillinghast finds many garden spider webs stretched vertically among the tall grasses. Typically, the large yellow and black spider hangs upside down in the center of the web, with heavy zigzag "writing" above and below. When startled, she clings to the web and vigorously pumps it up and down like a trampoline.

Approaching an empty web, Tillinghast explains that this spider, already spooked, is lying in wait in the grass below, connected to her web by a silk "lifeline." (Although most spiders have eight eyes, their vision is poor, and they rely on vibrations to detect the arrival and whereabouts of their prey.) Suddenly a small grasshopper crashes headlong into the web, and the spider shoots up to the center, flips upside down and darts out to grab her prey. Using her pointy hooked feet, she rapidly spins the grasshopper over and over as silk flows from her spinnerets like jets of spray from a crop-duster airplane. With the grasshopper safely straitjacketed, the spider sinks her fangs into it and then retreats, waiting for it to become paralyzed before returning to inject her saliva, which "predigests" the insect into a meal she can sip at her leisure.

Fearless of a spider's touch, Tillinghast scoops up one with his bare hand and allows it to roam up the front of his T-shirt, onto his bare arm, skirting the open edge of the sleeve, and then around on his back and out of sight. Eventually, he plucks it off and traps it in a translucent cup with a sprig of vetch. Although he is a predator of these predators, he avoids killing spiders if possible and clearly regards them with a sense of wonder. He'll never forget the first time he and Mark Townley '84, '93G, now a UNH instrumentation scientist, stayed up all night to find out when the garden spiders in his lab would start the daily task of eating the old web and spinning a new one. It was 4 a.m. when all the spiders, each in its own Plexiglas home, began to consume their webs in unison. "It was as if the 'Sorcerer's Apprentice' had been struck up," says Tillinghast.

King baboon spider exhibiting aggressive behavior.

When Tillinghast returns to the lab from his field trip, he scoops a spider out of its capsule and carefully holds it upside down, pinning its legs gently to its sides, except for the front two, which keep reaching out into the air. The disturbed spider emits some of its digestive fluids, as brown as tobacco juice, which Tillinghast catches in a tiny pipette. Then—careful to avoid the reflex tendency to suck in—he blows the contents into a tiny plastic test tube for chemical analysis.

Working with Matthew Foradori '99G, '03G, now a biologist at Edinboro University in Pennsylvania, Tillinghast and Townley have found that spiders have a powerful battery of enzymes in their digestive fluid that can dissolve tissues. There is a chemical in its blood, however, that inhibits those same enzymes from dissolving the spider.

Untangling the Web
Spider silk is five times stronger than steel, weight for weight, and five times more elastic than Kevlar. Unlike manmade synthetics, it is produced at roughly ambient temperature and pressure, and it is also recycled by being consumed by its producers. If humans could find a way to produce a similar material, there could be a slew of applications, including bullet-proof vests, medical sutures, artificial tendons, airplane parts and biodegradable fishing lines. In addition, spider venoms contain whole catalogs of chemicals. Many have yet to be identified, but some are being tested for uses ranging from pain killers to a treatment for erectile dysfunction.

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