Book 11, Question 17
Why Do Worms Not Have Fur, Feathers, or Scales?
Worms have no fur, feathers, or scales because they breathe through their skin! An earthworm's skin has to stay thin and moist so air can pass through. A coat would only get in the way.
More fun facts
- Earthworms need soil that is at least as damp as a wrung out sponge, and if their skin dries out they cannot breathe.
- Too much water is also a problem, because waterlogged soil pushes out the oxygen worms need.
- A worm's body is wrapped in a thin, moist outer layer called a cuticle, with tiny hair-like bristles called setae poking out.
- Earthworms move using their setae, which grow in pairs on each segment of the body.
- The scientific name for earthworms' group, Oligochaeta, means few bristles, and Annelida, the larger group, means little ring.
- The mucus from earthworm skin helps glue soil into crumbs, which improves soil structure.
Sources: Illinois, Colostate, earthwormsoc.org.uk, animaldiversity.org
Questions kids ask
Why do worms feel slimy?
Their skin makes mucus that keeps it wet, which they need because they breathe through their skin.
Can a worm drown?
Yes. Worms need damp soil, but if the soil is waterlogged, the oxygen is pushed out and they cannot breathe.