Spiders

Spiders
By Chris

What makes a spider a spider?
A spider has two main parts to it, unlike insects which have 3. The back part is called the abdomen. This contains the heart and the spinnerets. The other part is called the cephalothorax which contains the eyes, fangs, brain, stomach and two short arms which a spider uses to hold it's prey.
From: spiders by Nic Bishop

Spider's Webs
A spider makes it's silk with spinnerets. A spider web is made by using silk. For its size the silk is stronger than steel. So next time you brush away a cobweb, consider what you're brushing. The diameter of a strand is around 1/10,000 of an inch. Human hair has 30 times that diameter and a thousand times the cross-sectional area. It's the difference between thread and rope.
From:
http://www.uh.edu/engines/epi1069.htm

Not just 2 eyes
Everyone knows that spiders have 8 legs but do you know that most spiders have 8 eyes? But a spider can not see as clearly as you. Their eyes are very simple. Spiders normally know when something is nearby but they can't see shapes.
A few spiders have no eyes at all. They live in caves where it is completely dark but they can use their web to detect the motion of prey.
Picture from:www.eurospiders.com/spider_eyes.jpg
Info from:
Spiders by Nic Biship

How spiders eat.
Spiders eat in an unusual way. They don't chew and swallow, they drink. First the spider stabs it's fangs and injects poision to stop it moving. Then it dribbles digestive juices on it's meal. This turns the animal's insides into soup. After the spider has finished it's meal all that's left are empty bits of skin and sometimes wings.
From: spiders by Nic Bishop

Types of spiders
There are more 38,000 different types of spiders that we know of. Some spiders are as little as a dust mite. Others are as big as a foot. Tarantulas are known as the kings and queens of ambush. The biggest is the Goliath birdeater spider found in South America. The most poisoness is the black widow spider. Jumping spiders are able to jump 20 times their own body length.
From: www.extremescience.com/BiggestSpider.htm
and
Spiders by Nic bishop

Katipo spider
New Zealand's most poisoness spider is the Katipo spider. Body length about 8 mm. Katipo is a New Zealand native, closely related to the Australian Redback. They are found only near the seashore under drift wood or associated with coastal grasses. Their bite is poisonous but an antidote is available at hospitals .
From: http://www.landcareresearch.co.nz/research/biosystematics/invertebrates/invertid/bug_details.asp?Bu_ID=55

Spider Relatives
All Spiders are Arachnids but not all Arachnids are spiders.
There are mainly five common arachnid families. Apart from Araneae (Spiders), these are: Acari (Ticks and Mites), Opiliones (Harvestmen), Pseudoscorpiones (Pseudoscorpions) and Scorpions.
From:
jpg - www.eurospiders.com/spider_eyes.jpg

The End