Grades K–2 · Organisms
Why does a hedgehog curl into a spiky ball?
A hedgehog has stiff spines across its back. These are special thick hairs. Its face, belly and legs have softer coverings that are easier to reach when it is stretched out.
In the diagramCurling puts spines on the outsidesoft parts exposedsoft parts tucked in
When threatened, the hedgehog can tuck its head and legs inward and curl its body. Muscles pull its skin into a rounded shape. The spiny back then faces outward around the ball.
A hunter meets the pointed covering instead of the soft belly. The spines stay attached to the hedgehog; they are not arrows. Curling changes which parts of the animal are exposed.
About this explanation
Starting knowledge: Recognize soft skin and a stiff pointed covering.
Sources
- San Diego Zoo Wildlife Alliance — Hedgehog