Previously unknown species of clams, mussels, crabs, jellyfish, and other animals have been discovered in the rift communities. A species of blind crab is a common scavenger in some areas. Colonial jellyfish were also discovered attached to the bottom by stalks and bearing yellow spheres looking much like dandelions. Although the members of rift communities have close relatives that inhabit the warmer, sunlit seas, many are species new to science. Rift communities have been discovered on other parts of the ocean floor and presumably could occur wherever fissures are formed by the separation of the Earth's crustal plates.
Some species are common to rift communities separated by thousands of miles of cold, dark ocean.
Each community discovered so far, however, has a unique assemblage and diversity of species. The discovery of rift communities created much excitement in deep-sea biology. Knowledge of the behavior and ecology of most deep-sea species is scarce because of the difficulty of observing and studying animals at great depths in the ocean. The Learning Company, Inc.