SPIDERS

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Arachnophilia
Love of spiders

Are you an arachnophobe or an arachnophile?

In the stories the ancient Greeks told there was a girl called Arachne.

She was a wonderful weaver of cloth and spinner of thread.

The Goddess Athena saw her work and was jealous.

She turned poor Arachne into a spider to weave webs for ever more.

We now call spiders Arachnids after Arachne.

==**Some examples of spiders:**
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* Wolf spiders lie in wait, hoping for an insect to pass by. They have very good eyesight.

Spiders can have eight eyes.

A tarantula is a wolf spider.

They get their name from the town of Taranto in Italy.

People who were bitten by a tarantula were supposed to do a wild dance called a tarantella because of the pain of the bite.

Tarantulas live in silk burrows in the soil.

Although North American tarantulas are very poisonous, European tarantulas are less poisonous than is usually believed.

* The spider that you see in the garden with a white cross on its back builds an orb web.

They sit at the edge or in the centre of the webs waiting for prey to stumble into the sticky threads.

The spider will feel the web shake.

As the prey struggles in the web the spider will rush out from its hiding place and bite the insect with a paralysing poison so that it cannot move.

Then the spider will wrap it up with silk to make a parcel.

* Funnel web spiders have a flat web with a tunnel at one side where the spider lurks.

The big spiders you see in the bath are funnel webs.

* The Bolas spider spins a thread with a sticky drop at the end which it swings around trying to catch moths that fly by.
* Spiders live in many habitats.

For example, the raft spider lives on the surface of the water and moves around by rowing with its legs.

## **Body Parts:**

Spiders have very different bodies to us humans.

They have eight, or sometimes six, eyes.

Their fangs are for injecting poison into the prey.

They have four pairs of legs.

They also have two palps next to the mouth.​​​​​​​

The palps handle the prey and are used by the male during mating.

The rear part of their body is called the abdomen.

At the very end of the abdomen are the spinnerets that spin the silk to make webs.

Spiders have a hard outer shell made of a substance called chitin.

Spiders moult these shells as they grow inside them.

Their bodies are soft inside the armour plating.

This armour is called the exoskeleton.

When it is time to change its shell, the exoskeleton cracks and the front of the spider emerges.

Gradually the old shell is left behind.

Once free of it the spider flexes its legs otherwise the joints would seize up.

The whole business takes *10-15* minutes in small spiders and several hours for a large tarantula.

Sometimes the male is very much smaller than the female.

The male lives shorter lives too.

## **Feeding:**

When a spider bites the fangs pierce the prey and poison flows down the fang into the victim.

After being bitten and wrapped in silk the spider spits digestive fluid onto the prey.

This turns the prey into liquid and after a few minutes it is sucked up by the spider.

There are only *20-30* species of spider in the whole world that are dangerous to humans.

There are none in this country.

## **Mating:**

Often the male sits at the edge of the female's web and plucks the silk to get her attention.

Spiders are very sensitive to vibrations.

To get the female to mate with him the male must court her.

The method varies from species to species but it can include drumming with the palps and displaying by raising and lowering the body.

If a male courts at the wrong time he could be eaten by the female.

When the female's eggs are laid, they are wrapped in silk cocoons to protect them.

Sometimes the eggs hang suspended by a thread.

## **Silk:**

Spider silk is wonderful stuff and it is used by the spider in many different ways.

It is spun, rather like toothpaste being squeezed out of a tube, through the spinnerets at the end of the abdomen.

The silk comes from glands inside the spider and the different types of silk can be spun for different uses.

The female cross spider can make seven types of silk.

For example, threads on the web have blobs of glue on them to catch insects.

Sometimes a spider will eat its old web and recycle the silk.

Spider silk is nearly as strong as Kevlar which is the material used to make *bullet-proof* vests.

## **Webs:**

There are several different kinds of web.

Each species makes its own type (*see picture*).

* The tangle (1) is a mixed up maze made, for example, by the black widow spider.
* The sheet (2) is a flat sheet of silk with threads holding it above and below.

This can be changed into a bowl shape, a hammock, or a dome depending on the species building it.

* The funnel (3) is a sheet of silk with a tube or funnel at one side where the spider hides.

When the prey lands on the web the spider feels the web shaking and runs out to paral

    yse the insect with its bite.

The spider then wraps the prey in silk and takes it into the funnel to eat.

* The orb web (4) is the kind of web we most commonly see and link with spiders. The spider anchors silk lines, that radiate from a centre, to grass and bushes.

It then weaves a sticky spiral of silk around the centre.

Threads are woven round to strengthen the outside.

The sticky threads attract water from the air, making droplets.

Where two threads cross they stick together.

*Orb-web* spiders usually build their webs by night, and do it by touch, not sight.

A baby spider automatically knows how to build a web.

All these different types of web are to catch a meal for the spider that builds them.

## **Spider Stories:**

In the year 1306 Robert the Bruce was fighting to remove the English and their king, Edward I, from Scotland. Robert was hiding on the island of Rathlin.

He noticed a spider trying to fix its web to a beam.

It failed six times.

Robert watched a little longer and the spider succeeded on the seventh attempt.

He took courage from the spider's example and finally beat the English at the battle of Bannockburn.

So comes the saying "Try, try, try again!"

Mohammed and the spider.

Spiders are seen as lucky.

When Mohammed fled from Mecca he hid in a cave to escape the Koreishites who were chasing him.

Suddenly an acacia tree in full leaf sprang up at the mouth of the cave.

There was a wood pigeon's nest in its branches and a spider had woven its web between the tree and the cave.

When the men who chased Mohammed saw this, they believed that no one could have entered the cave recently and they ran on by.