Beginning of Essay
Rocky shores are found all over the world, yet they are not the same. For example, on the Pacific Northwest coast you will find steep, rocky cliffs. In Maine you will find rocky coasts, too; however, they slope gently to the sea. They generally occur where there ....

Middle of Essay
.... was formed by successive flows of lava into the sea which have not had time to collect sediment. Life on the rocky shores is separated into distinct zones that reflect the length of time each is exposed. At the highest point on the rocks is the black zone, marked by blue-green algae. This transition area between land and the marine environment is flooded only during the high spring tides. The algae, enclosed in gelatinous sheaths to resist drying, are grazed on by periwinkles, which are protected under tightly sealed, conical shells. Below the black zone lies the white zone, where barnacles are tightly glued to rocks. Living among the barnacle ....