Plate tectonic history and hot vent biogeography

Abstract Since the 1977 discovery of hydrothermal vents and their extraordinary fauna, vents have been discovered along mid-ocean ridges in the eastern Pacific, on the Mid-Atlantic Ridge and on the spreading centres behind western Pacific subduction zones. The dependence of these habitats on plate activity suggests that plate history may play a strong role in their evolution. As few of the species known from vents are found in other marine habitats, an examination of biogeographic patterns with respect to plate history is feasible. An examination of taxon overlap with other sulphide-rich habitats (seeps and whale carcasses) suggests that a minority of faunal elements have common ancestors. Proximity of vent sites to each other does reflect regional similarities but it is the distance along ridge pathways and vicariant events that appear most important. An understanding of the tectonic history of our oceans provides a framework for predicting the composition of vent communities in unexplored areas.