'The adult mussel and the adult barnacle are both filter feeders. They live in the intertidal zone of a rocky seashore.
They can be found attached to rocks and stones. The adults do not move once they are attached to a solid surface. When the tide is in the
seawater covers both animals and they start to feed. The barnacle is surrounded by a hard, chalky cover and the mussel lives inside two
halves of a tough shell.'