Antarctic Paleogene Terrestrial Mammal Biogeography: Vicariance, Dispersal and Geological Events.

REGUERO, M.; ABELLO, M. A.; POSADAS, P.; ORTIZ-JAUREGUIZAR E.; GELFO, J. N.; CHORNOGUBSKY, L.

Goa

Simposio; XII International Symposium on Antarctic Earth Science; 2015

SCAR

From the results obtained we conclude that the biogeographic histories of eutherians(Astrapotheria and Litopterna) were different from those of metatherians (i.e. Polydolopidae), but all of them support the hypothesis of an early stage (late Paleocene) of the paleogeogeographic event leading to the development of a shallow epicontinetal sea which might be interpreted as the earliest tectonic phase (Paleocene) that eventually later led to the opening of the Drake Passage (Miocene). These analyses reveal biogeographical patterns that closely correlate with palaeogeography. The conclusions drawn from the biogeographical analyses of two eutherian and one metatherian clades reinforce the hypothesis that vicariance and dispersal patterns documented in the early Paleogenebetween West Antarctica and Patagonia are linked to geological events like an early stage of rifting produced stretching causing crustal thinning and widespread subsidence during the Paleocene leading to the development of a shallow but wide epicontinetal sea.