The spider comes to the surface, traps a bubble of air, dives down with the bubble, and releases it under the little canopy. Before long, the silk sheet looks like a deep umbrella top, filled with air. Here, the spider lives its life, resting, eating and reproducing. Whenever the spider needs more air, it simply goes to the surface to fetch another bubble.

Horseshoe crabs and spiders are actually close relatives. The horseshoe crab belongs to the large group of invertebrates (animals without backbones) called Arthropods. This group also includes lobsters, crabs, insects, spiders, and scorpions. Even though it looks crab-like, with a hard shell and claws, the horseshoe crab is more closely related to scorpions and spiders than to crabs.

Many cultures believe that spiders bring good luck. The spider "was popular with the Romans, who had a favorite mascot in the shape of a precious stone upon which a spider was engraved. Also they were fond of carrying little spiders of gold or silver, or any of the fortunate metals, to bring good luck in anything to do with trade."

The idea that to kill a spider will bring bad luck is common still, and most housewives, while destroying the web, will carefully lift the spider and put it out of doors. That killing a spider is followed by monetary loss is the belief in some parts of the country, thus particularizing the kind of ill luck to be expected. But to see a spider is fortunate so long as it is not hurt." Spider silk can stretch up to 50 percent of its original length. A strand of spider silk the width of a pencil could stop a Boeing 747 in flight.

On average, people fear spiders more than they fear dying. However, statistically, you are more likely to be killed by a champagne cork than by the bite of a poisonous spider.

We'd probably all be dead without spiders. Their sheer number makes spiders vital in maintaining the balance of nature. Because they structure insect communities wherever they occur, spiders play a vital role in the terrestrial food chain. Without all those hungry spiders, insect populations would explode, food crops would be decimated, and ecological balances ravaged. Humans would probably starve within a matter of months--if they hadn't already succumbed to various insect-borne diseases. No spider, incidentally, has been found to transmit disease. Silk + Venom = Extraordinary Evolutionary Success.

Two attributes--silk and venom--have contributed to the spider's key position in the food chain (not counting their prodigious appetites). Scientists are working to put all to use. The ancient Greeks used spider silk very effectively to staunch bleeding wounds, as have soldiers in the Vietnam War and other modern conflicts. (The silk is so fine that it actually traps the blood platelets.)

Spider venom can be used to treat certain neurological and mental disorders. A research group in Utah has isolated components from the venom of many species of North American spiders, which may help reduce brain damage following strokes.

Research is also being done into putting spiders to work in on the farm, to control insect pests. One problem is that while agriculturists generally want a very specific pest eliminated, spiders will eat just about anything, including other spiders on the job.