•A volcano shaped shell and permanent attachment allows barnacles to survive high wave action.

• A watertight shell with a moveable top allows the barnacle to open and close in response to environmental conditions.

•Specialized feet allow the barnacle to collect food particles.

•They are hermaphroditic which allows them to reproduce with their closest neighbors regardless of gender.

•They can breathe when exposed and when they are submerged.

•They can survive temperature extremes by using seawater trapped inside their shell to prevent freezing and for evaporation for cooling

•A high reproductive rate and brooding of eggs ensures barnacles have new populations every year.

•Byssal threads anchor the mussel to the intertidal rocks and a specially shaped shell allows it to survive high wave action.

•They can seal their shell tight when exposed trapping water inside, which helps them breathe when the tide is out.

•A small foot helps it move from one area to another.

•The mussel has the ability to grow quickly.

•They can survive temperature extremes by using seawater trapped inside their shell to prevent freezing and for evaporation for cooling

•By releasing millions of eggs, mussels ensure that some of their young will survive.