Spiders

Moreover, both of these venomous species have striking field marks making them easy to identify. If you acquire a spider field guide, the first thing you need to do is to look up these two species, notice the widow's "red hour- glass," and the recluse's "violin," and henceforward keep your distance from spiders with those marks.

If spiders can be so dangerous, do they really make good subjects for EarthFooters?

You bet! You just must be a little careful. Wandering around checking out spiders, and paying attention to what you're doing, is certainly less dangerous than hopping into the family car and heading for the local mall. Just follow this one simple rule and you'll have no problem:

Don't handle them!

Usually when you spot spiders they're perched unmoving in or near their webs, or else they're moving slowly across the ground, and are likely to stop to look up at you if you get onto your elbows and knees to look down at them. You gain nothing by attempting to hold them, so just don't do it.

However, you can draw close enough to get a good view of them, especially if you have a good magnifying glass. In our "Tools" section we said that small hand lenses usually make the best magnifying glasses. Sometimes with spiders the larger, lollypop-type reading lens with a stick handle is more useful, because you can look at them from farther away.

How does spider watching compare with, say, bird watching?

For one thing, many more species of spider exist than species of bird. About as many spider species exist just in New York and New England as there are bird species in all of North America north of Mexico. There's no pocket-size field guide we can carry with us, expecting to identify every spider we meet, as we do with birds. Amateur spider watchers must forgo the pleasure of making lists of every spider species seen.

There's at least one small, commonly available field guide illustrating and describing the most common spider species, many of them the very ones found in our backyards. It's one of the Golden Nature Guides, almost always available in mall bookstores, called Spiders and Their Kin, by Herbert and Lorna Levi, and published by Golden Press of New York. There could hardly be a better first introduction to spiders than this.

If later you become a real spider enthusiast, you can graduate to one of the "Pictured-Key Nature Series," called How to Know the Spiders, by Kaston. This series is published by Wm. C. Brown Company Publishers of Dubuque, Iowa.

Once you begin looking closely at spiders, one of the most exciting of your first discoveries will be that many, maybe most, are extraordinarily pretty. Even if at first glance they look "small and brown," once you've focused your magnifying glass and are squinting hard, you'll probably see that the body is ornamented with spots, stripes, arabesques, and/or other strange designs. Many spiders are brightly colored, and some are even shaped like psychedelic witch-doctor masks.

Spider bodies are fundamentally different from those of insects. Insect bodies generally are divided into three main parts -- the head, the thorax in the middle, and the abdomen at the end. In spiders, the rear-end abdomen is still there, but the first two segments, the head and thorax, now are fused into a single unit referred to as the cephalothorax, cephalo being from a classical Greek root meaning, of course, "head."

Spiders possess eight legs, in contrast to insects, who possess only six. Also, many insects have compound eyes consisting of perhaps hundreds of small eyes, but nearly all spiders just have eight eyes. At the spider's rear end there are tiny spigot-like projections called spinnerets, from which spider silk is extruded.

There's a rainbow of ways that male spiders meet females. Often courtship rituals include dancing and leg-waving. However, the most bizarre part of spider reproduction is that of the spider sex act itself.

The male spider, as is typical among arthropods, possesses nothing like a penis. Therefore, how does the male's sperm enter the female's body? It's with the help of little leg-like appendages at the male spider's head, called palps. Before the male goes searching for a female, he deposits a droplet of sperm on a scrap of silk, sucks this into his plunger-like palp, and keeps it handy as he sets off looking for a female. Once he's found his mate and courtship has proceeded satisfactorily, during the mating process the male reaches beneath the female's abdomen with his palp and inserts the sperm through a slit there. From that point, the sperm pass to the eggs more or less as you might expect.

Often you hear that, after mating, the male spider is eaten by the female. That's true in only a few species. However, it is true that, in many species, once the male has mated, from nature's point of view he's no longer of value, so he forthwith "dies of natural causes."

Maybe nothing is as special about spiders as their use of silk. The females of most species construct silken cases in which they deposit and guard their eggs, and some species make silken nurseries for their babies, or spiderlings. Most spiders, even if they don't construct webs, lay down silk draglines as they walk; these can help the spider find its way back home, or serve as a safety line in case the spider falls from something.

Especially in the fall, spiderlings are apt to climb to the top of almost any tall weed, bush, or fence post, and extrude strands of silk into the wind, rather like releasing a kit into the air. As the silk lines lengthen, the wind tugs harder and harder on them, until finally the spiderling releases its hold on its platform, and the wind bears silk lines and spiderling to new territory -- perhaps just to the next bush, or maybe to the next county or state. This manner of traveling is called ballooning; in the fall, when the blue sky is streaked with silvery streaks of sunlight reflecting from ballooning spiderling silk, the bright streaks are called gossamers.

Many spiders, most notably the large, hairy wolf spiders likely to be spotted roving across our backyards as they hunt, and crab spiders, found inside flowers waiting to ambush insects coming for nectar, build no webs. However, there are plenty of spider species that do construct webs, and you'll soon discover that every web-making species produces its own distinct web design.

In fact, with practice you'll learn to look at a web and know which species or general kind of spider constructed it, without seeing the spider at all. For example, the large, spectacular Black and Yellow Argiope, sometimes called the Garden Spider, (Argiope aurantia) common in much of the U.S. and Canada, produces an orb web with a vertically zigzagging patch of silk in the web's center. The web at the right is a "sheetweb," the kind made by the common Bowl and Doily Spider, Frontinella communis.

In many backyards, the most conspicuous "spider" isn't a spider at all, but rather something related to the spiders, as are scorpions, ticks, mites, centipedes and millipedes. This is the Daddy-long-legs, also known as the Harvestman. These critters, which are perfectly harmless, possess little egg- shaped bodies with extremely long, slender legs that when spread out can cover most of a hand's palm. Never pick one up by the leg, however, for their legs come off very easily.

If you look at the body of a Daddy-long-legs with your magnifying glass, you'll see why this animal is not a spider. First of all, instead of the spider's two body parts, the cephalothorax and the abdomen, there's just one thing; its head, thorax, and abdomen are all fused together. Second, instead of the spider's usual eight eyes, it possesses just two.

Once you watch Daddy-long-legses long enough, you might notice that there's a smaller-bodied, long-legged form, and a larger-bodied, shorter-legged one. The small-bodied, long-legged one is the male. There are over a hundred Daddy-log-legs species in North America north of Mexico!

On the Web, you can find lots of spider info at the , in Belgium, and at a site in the Netherlands called .