WORMS

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WORMS
EWW, AAH, ICK SCIENCE EXPLORATIONS
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WORMS

• Making science fun is essential.
• Kids learn more when they are having fun.
• Teaching is more enjoyable when the kids are
  having fun.
• Fun is good.
• Worms are fun.
• Try it!

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What can you teach with worms?

• Ecosystems
• Food chains and webs
• Life cycles
• Adaptations
• How the earth changes
• Decomposition
• Qualitative and quantitative data collection
• Inquiry
• Teacher guided
• Student guided

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I LOVE WORMS!

• Worms require much less daily care than
  typical class specimens and they provide endless
  opportunities for learning about cycles, systems,
  decomposition, food, soil, science inquiry, and
  basic ecological connections.

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• Darwin declared that no other animal has played
  so important a part in the history of the world,
  as have these lowly organized creatures.
• Children love digging into the world of
  earthworms and it is a remarkably fun way to
  teach scientific inquiry.
• You must be prepared to get down and dirty if you
  really want to dig into an intriguing annelid
  investigation.

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Oligochaetology

• Kingdom Animalia
• Phylum Annelida
• Class Oligochaeta
• Segmented worms make up the Phylum Annelida. The
  phylum includes earthworms and their relatives,
  leeches, and a large number of mostly marine
  worms known as polychaetes.
• Annelids can be told by their segmented bodies.
  Polychaetes (meaning "many bristles") have,
  predictably, many bristles on the body, while
  earthworms and leeches have fewer bristles. There
  are about 9000 species of annelid known today.
• Eisenia fetida and Lumbricus rubellus
• Classification of earthworms is confusing. These
  two worms are commonly named redworms or red
  wigglers. They are both good composting worms.

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Anatomy/Physiology

• Worms are cold-blooded invertebrates. They can
  live in cold temperatures by hibernating or
  burrowing deeper into soil
• Worms have no eyes, but can sense light and feel
  vibrations in the ground.
• They have no lungs. They breathe through their
  skin.
• Worms come to the surface when it rains to find
  food, not because they're drowning!
• A healthy worm can eat up to 1/3 of its body
  weight in one day.

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• The saddle like bump in the middle of the worm is
  called the clitellum.
• A worms body is covered in mucus. This helps
  with respiration. Worms also secrete mucus to
  form cocoons for babies and as a defense
  mechanism. Mucus also helps line the tunnels they
  make so the dirt doesn't collapse on them.
• Worms move by using the setae (bristles) on their
  bodies, which act as little arms helping them
  push forward.
• If you cut an earthworm in half you don't get two
  earthworms. Only the front end will survive and
  will re-grow a tail end.
• Earthworms vary in size.

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Eating

• What do earthworms eat?
• The remains of living things that are in the
  soil.
• Worms are decomposers eaters of decaying
  material.
• They enjoy leaves and roots, kitchen leftovers
  and sometimes decomposing animals.
• Worms also eat living organisms (bacteria,
  fungus, etc).
• How do earthworms eat?
• They don't have teeth but have very strong mouth
  muscles
• They eat small pieces of food at a time.
• They also "swallow" soil as they burrow and
  extract nutrients from it.

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Earthworm Ecology

• Increase pores in the soil (deeper and faster
  penetration of water and oxygen) "open up soil."
• Tunnel deeply in the soil and bring deeper soil
  closer to the surface, mixing it with the
  topsoil.
• Slime, a secretion of earthworms, contains
  nitrogen, an important nutrient for plants.
• Earthworm poop "casts". Makes soil more
  fertile. It contains concentrated nitrate,
  phosphorous, exchangeable magnesium, potassium
  and calcium -these plant nutrients, help
  regulate soil pH.
• Can be used for composting to break down food
  waste, yard waste, to create gardening soil.
• Food for others. What eats them? Snakes, birds,
  moles, toads, foxes, beetles, centipedes,
  leeches, slugs and flatworms.

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Factors to consider when designing or guiding
worm investigations

• Light vs dark
• Even though worms dont have eyes, they can sense
  light, especially at their anterior (front end).
  They move away from light and will become
  paralyzed if exposed to light for too long
  (approximately one hour).
• Wet vs Dry
• If a worms skin dries out, it will die (breathes
  through skin requires moist skin). Also it is
  easier for worms to move in wet environments.
  Worms can drown.
• Cold vs Warm
• Worms can freeze. They are cold-blooded.

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WORMS

• Making science fun is essential.
• Kids learn more when they are having fun.
• Teaching is more enjoyable when the kids are
  having fun.
• Fun is good.
• Worms are fun.
• Try it!