Biological groundwater studies in Ascension Island (South Atlantic), October — November 1989

Ascension Island (08° S 14°25’ W) occupies a very peculiar place in our current research project on the biological properties of ground waters of the the Mid-Atlantic islands: -- The island lies closer to the equator than any of the other Mid-Atlantic islands. -- The island lies almost on the Mid-Atlantic Ridge, and far remote from any other insular or continental region. -- The island’s subaerial part consists of very young volcanic outcrops (dated radiometrically at 1-2 My). Through these properties, the comparison of Ascension with the intensively studied Canary Islands (see the series of publications of our team under the collective title “Stygofauna of the Canary Islands”, parts 1 to 19) is of great importance for a better understanding of dispersal and/or vicariant processes in the evolution of insular groundwater organisms (or stygobionts as these are called scientifically).