Organisms living in this zone have a highly variable and often hostile environment, and have evolved various adaptations to cope with and even exploit these conditions. One easily visible feature of intertidal communities is vertical zonation, where the community is divided into distinct vertical bands of specific species going up the shore. Species ability to cope with abiotic factors associated with emersion stress, such as desiccation determines their upper limits, while biotic interactions e.g.competition with other species sets their lower limits.