Global Cambrian trilobite palaeobiogeography assessed using parsimony analysis of endemicity

ALVARO, J.J.; AHLBERG, P.; BABCOCK, L.; BORDONARO, O.L.

GEOLOGICAL SOCIETY OF LONDON SPECIAL PUBLICATION

The Geological Society of London

Lugar: London; Año: 2013 vol. 38 p. 273 - 296

0305-8719

Palaeobiogeographic data on Cambrian trilobites obtained during the last century are combined in this paper to evaluate palaeoceanographic links through c. 30 my, once these arthropods biomineralized. Worldwide major tectonostratigraphic units are characterized at series intervals of Cambrian time and datasets of trilobite genera (631 for Cambrian Series 2, 969 for Cambrian Series 3, and 868 for the Furongian Series) are analyzed using Parsimony Analysis of Endemicity (PAE). Special attention is given to the biogeographic observations made in microcontinents and exotic terranes. The same is done for platform-basinal transects of well-known continental margins. The PAE analysis resulted in distinct palaeogeographic area groupings among the tectonostratigraphic units. With these groupings, several palaeobiogeographic units are distinguished, which do not necessarily fit the previously proposed biogeographic realms and provinces. Their development and spatial distributions are broadly controlled by Cambrian palaeoclimates, palaeogeographic conditions (e.g., carbonate productivity and anoxic conditions), and ocean current circulation.