The Ediacaran White Sea Biota in the Central Urals

摘要

The mass appearance and increased rates of diversification of the Metazoa during the Cambrian were attended by the installation of two novel levels, the macrobenthos and the nekton, in a cascade of trophic relationships in marine paleocommunities. Assessing the structure and functioning of the ecosystem at early stages of the metazoan evolution is, therefore, of fundamental importance, and here the late Proterozoic Ediacaran fossil biota provides an invaluable source of information. The stratigraphic and taxonomic accuracy of planetary-scale analyses of Ediacaran biodiversity has been hampered by a poor understanding of the role of local paleobiogeographic, paleoecological and taphonomic factors in Ediacaran fossil distribution. This is because all Ediacaran fossil localities are represented by comparatively small outcrops that provide rather limited insight into paleocommunities on geographically isolated habitat patches. This paper presents a pilot attempt at reconstructing the paleobiogeographic area of Ediacaran distribution. It is the first time that this kind of approach has been applied to Ediacaran fossils. Here we report the occurrence of the White Sea fossil biota in the Central Urals that has revealed bio-geographic links between the spatially isolated Urals and the Southeast White Sea area, thereby suggesting Ediacaran dispersal over a distance of 1200 km.