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Earthworms
Earthworms live everywhere
in the world where there is soil.
Earthworms eat as they
burrow through the soil
Earthworms do not have
teeth
Earthworms help make the
soil healthy
Earthworms lay eggs
Worms are food for animals and birds
such as this kingfisher
Species
There are about 2 700 species (different kinds) of earthworms around the world.
Earthworm bodies
Earthworms are invertebrates, which means they don't have backbones.
Their soft bodies can be brown, pink or even red.
Did you know? In the Philippines there are blue earthworms and one kind in the United Kingdom is green!
Earthworms have a brain, 5 hearts and parts inside their bodies
which help them to breathe. The earthworm's body is covered with
chemoreceptors (say kee-mow-ree-sep-tuz) which is how the worm tastes things. Chemoreceptors
are tiny sense organs which detect chemicals in the soil.
Earthworm sizes
The smallest earthworms
are about 1 centimetre long and the largest can be 4 metres long.
One of the largest earthworms is the Giant
Gippsland Earthworm, found in one part of Australia. There
are large earthworms in South Africa too.
Earthworm Life Cycle
Earthworms are hermaphrodites (say her-maff-row-die-ts). This means that each earthworm has
male parts that produce sperm and female parts that produce eggs.
All earthworms lay eggs.
When two earthworms mate, they lie together, and cover themselves in sticky mucus, and pass sperm into each other's body. The sperm makes the eggs inside each earthworm's body grow.
A thick ring of slime forms around
each worm's body and 
as
the earthworm wriggles forward, the ring with eggs inside it slips
off and is left on the ground. The ring closes at both ends and
becomes a hard cocoon that protects the eggs.
The eggs hatch after two weeks if the weather is warm, but they can take up to three months to hatch when it is cold. Usually one or two earthworms hatch out of each egg. The young worms are about 12 millimetres long and light pink in colour. Earthworms are able to mate when they are twelve months old.
How earthworms
help soil and plants
Earthworms dig large burrows which let water and air into the
soil. 
This
helps stop erosion and lets the water and air get down to the
roots of plants. The burrows also helps plant roots to move more
easily through the soil and into new spaces. Worms drag leaves
and plant bits down into the earth. As they burrow, the worms
swallow soil and eat the plant matter that is in it. The soil
they swallow passes though the worm's body and is left in little
piles on top of the ground. This is called castings
and is excellent fertiliser (food for plants). People who farm
worms do it to collect the castings to sell to gardeners.
Click here and here to find out more information about earthworms
http://www.naturewatch.ca/english/wormwatch/about/ecology.html
http://yucky.kids.discovery.com/noflash/worm/pg000102.html
Click here for information about building a wormery in your backyard
http://www.geocities.com/RainForest/Andes/4996/worm_farm.htm
Remember: Always
acknowledge where you find information
If you use any of the information on this page acknowledge this
source in your bibliography like this:
Earthworms
(2003).
[Online], Available: www.kidcyber.com.au
updated August 2006