Changing palaeobiogeography during the Ordovician Period

Abstract

Owing to the increasing availability of data for many fossil groups and a generally accepted palae-ogeographical configuration, palaeontologists have been able to develop progressively more robust palaeobio-geographical scenarios for the spatial distributions of Ordovician marine faunas. However, most research in Early Paleozoic palaeobiogeography centres on data derived from extensively studied localities in North America and Europe. Thus, clear patterns are emerging of regional biogeography for these areas. However, the fragmentary nature of data from other regions hinders the development of a detailed understanding of palaeogeographical schemes of many clades at the global level. Provincial patterns are now available for several fossil groups, but the global coverage remains generally fragmentary. Palaeobiogeographical investigations were traditionally focused on better understanding of palaeogeographical scenarios and often employed quantitative analyses of faunal similarity. More recently palaeobiogeographical analyses have expanded to investigate questions such as the location and pace of speciation and macroevolution together with macroecological change. For example, studies on the evolution of speciation levels in the frame of the taxonomic radiation of the Great Ordovician Biodiversification are now available. Future investigations, including modelling, will provide more integrative, global patterns of provincialism, including the location of Ordovician biodiversity hotspots and the recognition of latitudinal diversity gradients.