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             Despite the evidence of the cobwebs that accumulate in our cellars and gardens, relatively few of the world’s spiders regularly weave webs. Most of them regards it as too laborious and risky a means of trapping their food. Webs give weaving spiders a monopoly of aerial prey, and they positioned them cunningly to take full advantage. But webs are easily broken, and building them exposes spiders to attacks by birds.

            Many Spiders rely on their mobility to hunt down food on the ground or to steer clear of danger. The common house spider, for example, is a fast runner, travelling proportionally six times as fast as an Olympic sprinter. Other spider lurk in burrows, trees and buildings until their prey comes to them,. These spiders are invariably more venomous that web-weavers, because they need to overpower their quarry more quickly, instead of leaving it to a lingering death, glued to the larder.

            Scientist says that the world’s 40,000 or so species of spider came originally from marine creature that invaded the land some 400 million years ago. Their evolution hasn’t resulted in earlier kinds dying out. Trapdoor and funnel-web spider, for example, have lived almost unchanged in form for millions of years. Ina a process known as adaptive radiation, more and more spiders of different kinds have developed, successfully filling every available ecological niche and porting a wonderful mix lifestyle.

            All spiders share predatory habit and unique method of mating. Te male spins a strand of web onto which he drops the sperm. He sucks the web and sperm in to organs known as palps, and then hunts for a female. Swiftly to avoid retaliation and possible injury, he discharges the sperm into her genitals, and makes his gateway. Spiders spin silk by squirting it from modified excretory glands. Originally the silk was used to protect eggs and to line nesting burrows. Now it serves many purposes. As well as webs, it makes trip lines to alert trapdoor spiders to approaching visitors, it wraps up prey: it provides safety lines for jumping spiders, so that if they fall they are suspended by a thread, much as mountaineers are saved by safety ropes. On slender strands of gossamer, hatchlings spiders, which number up to 1000 from one cocoon, can disperse by riding the wind.

Members of the worldwide Theridiidae family spiders, which include the American black widow, lay gum-footed lines on which to catch their food. First, they spin a tangle of web as a anchor, attaching it to the ground, a tree or a rock. Then they stretch a sticky thread to their hideout. An inspecting insect becomes caught on the line, and the spider hauls it in. Net throwing spiders weave a napkin of elastic silk, which they hold with their front four feet as they hang upside down, as their prey approached, they lung, capturing it in the net. The victim struggles serve only to imprison it more tightly. But for originally and simplicity nothing beats the ploys of tropical bolas spiders. The bolas spider dangles a large, sticky globule on the end of a single silk thread. The adhesive attracts moths. The spider senses a moth’s vibrating wings, and swings the lure, like a bolas, faster and faster. When it traps a moth on the sticky bait, the spider hauls it up, like an angler landing fish.

            Spider silk is extremely light and strong. A strand stretching from London to New York, a distance of 5536km (3440miles) would weigh less than a pullet’s egg, yet have a breaking strain proportionally greater that that of steel. The silk of the golden orb spider, found worldwide, is the strongest natural fiber known.

            Many plants park a powerful dose of poison, a fact known since earliest times. The ancient Greeks used infusion of aconite, an extract from the roots of monkshood (wolfsbane), to dispose of the aged and infirm. Spears dipped in aconite were deadly weapon in many ancient battles, causing sever and often fatal poisoning from just a scratch.        

            Until recent times, natives of Java used to smear hunting arrows with the deadly sap of the upas tree. Amazonian tribesmen coat their arrowheads in curate, which they get by boiling the bark of the pareira vine Chandrodendron tomentosum. Some East African tribesmen dip arrows in a toxin held in the wood and roots of Acokanthera plants. The poison also provides a crafty way to kill enemies. The spiny fruit of Tribulus terrestris, a form of caltrops are soaked in toxins and scattered along a likely path. A barefoot victim may scarcely notice the fatal prick, ant the tribe probably decides that death was from natural causes.

            Georgi Markov, a Bulgarian broadcaster in the BBC’s external service, dies mysteriously in London in September 1978, after being prodded accidently. It seemed at first – with another pedestrian’s umbrella. Investigators decided he’d been murdered. The umbrella spike, they deduced, carried a shot of ricin, a deadly derivative of the castor-oil plant.  Most of the people know that some mushrooms are highly toxic. Without swift medical attention eating the cap Amanita phalloides is fatal in 50% of cases, but for its grim effects, a microscopic fungus called ergot is in a class of its own. The fungus sometimes infects rye. Bread made from the rye is poisonous.

            In AD 994 some 40000 people died in France from ergot poisoning. At the time, it was believed a deadly plague had swept the land. Those who sought sanctuary in monasteries and convents survived because monks and nuns made bread from wheat flour. A peculiar form of madness overcame visitors to the German town of Aachen in 1374. They had survived there to celebrate the mid-summer feast of St John, and for no reason started top dance. Foaming at the mouth, they dance until they dropped. In the nest 50yrs, dancing mania spread. Many Historians today believed that rye bread infected with the ergot fungus as to blame. Some say that it caused the famous trials at Salem, Massachusetts, in 1692, after which fourteen women, mostly teenagers and five men, all of whom had hallucinations, were hanged as witches.

            Plant poisons come from many sources. The toxin in a cup of apple seeds could kill a man; surprisingly some creatures don’t suffer the poison’s effect. A tiny slug can eat a whole death-cap mushrooms that could kill at least three men. Cabbages, cauliflower and broccoli are highly toxic to most insects, but give a feast to aphids and caterpillars of the cabbage-white butterfly. Some animals have adapted to plants toxins. Grazing animals and most insets avoid the bitter poison of milkweed, but caterpillars of the monarch butterfly feed on it, storing the toxin in special tissues. Bird predators ignore the monarch, because they have learned that its stored poisons will make them vomit.