A new global palaeobiogeographical model for the late Mesozoic and early Tertiary

Late Mesozoic palaeobiogeography has been characterized by a distinction between the northern territories of Laurasia and the southern landmasses of Gondwana. The repeated discovery of Gondwanan lineages in Laurasia has led to the proposal of alternative scenarios to explain these anomalous occurrences. A new biogeographical model for late Mesozoic terrestrial ecosystems is here proposed, in which Europe and ‘Gondwanan’ territories possessed a common Eurogondwanan fauna during the earliest Cretaceous. Subsequently, following the Hauterivian, Europe severed from Africa and connected to Asiamerica resulting in a faunal interchange. This model explains the presence of ‘Gondwanan’ taxa in Laurasia and the absence of Laurasian forms in the southern territories during the Cretaceous. In order to test this new palaeobiogeographical model, tree reconciliation analyses (TRAs) were performed based on biogeographical signals provided by a supertree of late Mesozoic archosaurs. The TRAs found signi...