Why does a hermet crab live in shell?

A hermit crab lives in a shell because it does not have a protective outer shell of its own. Hermit crabs have soft abdomens that are vulnerable to predators and dehydration. To protect themselves, hermit crabs seek out and occupy empty seashells or other suitable shelters, such as pieces of coral or rock.

The hermit crab will move into a new shell as it grows larger. When a hermit crab finds a suitable shell, it will insert its soft abdomen into the shell and use its strong claws to grip the inside of the shell. Some hermit crabs may even modify the shell to make it a better fit.

By living in a shell, the hermit crab gains protection from predators and the elements. The shell also provides support and helps the hermit crab to maintain its body shape. Additionally, the shell can help the hermit crab to camouflage itself from predators by blending in with its surroundings.