wht animal don't swicth shells?

Answer 1

The only animal that does switch shells as it grows is the hermit crab; and the shells in this case are not really the crab's shell in the first place. They are the empty shells of dead snails, which the crab moves into and carries around with it, for protection. The crab cannot enlarge the shell the way the snail originally did, so when the crab outgrows a shell it has to find a bigger one and switch.