Learning to Like Spiders (or at least appreciate them)

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Cobweb Artistry

A more suitable sort of spider for casual study — and the type my sons and I are most fond of — are the everyday house spiders, more notoriously known as cobweb spiders. Actually, most cobweb weavers (there are some 200 different sorts in North America alone) spin their webs outside, in shrubs and grasses. But a few — the most common of which is the American house spider (Achaearanea tepidariorum) — prefer a home with a roof and walls. Their small bodies — bulbous and brown with black-and-gray splotches — are nothing special to look at, but you have to admire the little rascals for, if nothing else, their sheer industry.

At night, under cover of darkness, they emerge to build stringy, crisscrossed webs amid the angles of corners, floors, ceilings and woodwork. Like other arachnids, the house spider produces liquid silk in several glands, then draws it out through three to four pairs of spigotlike organs (called spinnerets) located in a cluster at the rear of its belly. The silk solidifies on contact with the air. A spider can produce different types of silk for different purposes — sticky, dry, thick, thin, elastic, rigid — depending on how it mixes and extrudes its internal chemicals.

Despite a random appearance, the web of a house spider actually is a well-constructed maze of silken guy lines pulled taut and firmly cemented to each other and to adjacent walls. Inner strands run every which way, creating a strong, sticky labyrinth from which few trapped insects ever escape. The spider spends most of its time hanging upside down on an extra layer of silk in the web, waiting patiently, usually near the center or off to one side. When an unsuspecting insect becomes entangled, the spider rushes to it, turns around and throws out a thick rope of silk to tie down the victim. Then the hunter bites, injecting a paralyzing toxin that ends the struggle for good.

At that point, the spider either hauls its catch back to its lair for later consumption, or eats it on the spot. Spider dining habits are decidedly gruesome — just the sort of thing we humans find endlessly fascinating. Instead of digesting its meal internally, a spider injects digestive juices into the victim’s body, then sucks up the liquefied flesh. Finally, probably not so much to tidy up as to keep its web invisible, the spider tosses out the shell and any remaining wings or legs.

Because cobwebs catch not only insects but also unsightly dust, they’re considered a nuisance and not something you want your in-laws to find when they come to visit. In 18th- and 19th-

century Europe, though, fresh cobwebs were once in great demand as bandages, for their ability to stem blood flow. In any event, you might want to consider leaving a spider (or two) with its web in your home, not just to help keep the fly, mosquito and moth populations down, but also because they’re fun to watch and study. You also could ..

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