Earthworm Species

• About 2,700 species– Nightcrawler (most

common, from Europe)– Manure Worm

(Compost Worm)– Green worm (can be

green, pink, gray, yellow)

– Snake worm (“Crazy worm”, very fast, from China)

Earthworm Anatomy• Cold-blooded• Invertebrates• No eyes (Light

sensitive)• Breathe through skin

-Can live underwater

•Feel vibrations through ground•Setae= bristles for moving •Can regrow tail•Mucus secretion

–Create stable tunnels

How long can they get?

• Depends on species• Compost Worms

– As small as 2 cm

• Nightcrawlers– Can be almost 1 ft!

• Longest Worm: South Africa– 22 feet from head to

tail!!!

What/How do they Eat?• Not just dirt, but the remains of living

things that are in the dirt! – Decomposers = eaters of dead material– Dead plants (leaves and roots) and dead

animals – Also eat living organisms (bacteria, fungus, etc).

• No teeth! Very strong mouth muscles– Eat small pieces of food– Also “swallow" soil - get nutrients from it – Nightcrawlers pull pieces of food into their

burrows to eat later.

Why Do We Like Earthworms?

• “Open up soil”– Burrowing– Oxygen and water

• Fertilize the soil– Burrowing mixes soil– Slime contains Nitrogen– “Casts” (earthworm

poop!)• Contains nutrients for

plants• Helps soil pH

• Composting• Food for other animals

Earthworm Life• How many are there in my

yard?– More than 1 million per

acre

• How long can they live?– Nightcrawlers about 6 years– Other species up to 10 years– If they don’t get eaten first!

Average life in wild = 2 yrs

• Hatch from cocoons– Can produce up to 80

cocoons per year (which could make about 240 babies)

What do earthworms like?

• Earthworms like to live underground in the soil.

• Do you think they would like an area that was light or dark?

What do earthworms like?

• Earthworms like to live underground in the soil.

• Do you think they would like an area that was hot or cold?

What do earthworms like?

• Earthworms like to live underground in the soil.

• Do you think they would like an area that was wet or dry?