Zonation

A group of university students study the zonation pattern of animals and plants on a marine rock platform, and the various physical and biological factors contributing to their distribution. At the highest tide level are blue periwinkles; then the barnacle zone, the worm zone and at low tide level, the cunjevoizone and then kelps. The ways in which various creatures protect themselves against dessication from sun and wind and against being washed off the rocks are shown.