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ABSTRACT The eastern coastal basins of Brazil are a series of small and isolated rivers that drain directly into the Atlantic Ocean. During the Pleistocene, sea-level retreat caused by glaciations exposed the continental shelf, resulting in enlarged paleodrainages that connected rivers that are isolated today. Using Geographic Information System (GIS), we infer the distribution of these paleodrainages, and their properties for the east Brazilian coast. Specifically, using elevation/bathymetric data for the largest sea-level retreats during the Pleistocene, the paleodrainages, their area and the number of contemporary basins connected by each palaeodrainage, was inferred. For the 145 inferred paleodrainages, total paleodrainage area is strongly correlated with the contemporary area encompassed by each paleodrainage, as well as with the number of contemporary basins encompassed by a paleodrainage. Differences in the continental shelf exposure along the coast affected the degree of past connectivity among contemporary rivers. With our results freely available, we discuss how paleodrainages have tremendous utility in biological studies, especially in regions with limited geologic data. With respect to the diverse ichthyofauna of the Brazilian coast, and its high endemism, we highlight how the inferred paleodrainages provide a backdrop to test hypotheses about the effect of past riverine connectivity on diversity patterns.

O estudo da glaciação plistocénica no Noroeste de Portugal tem interessado a comunidade científica desde finais do século XIX. Das várias serras minhotas, apenas a do Gerês e da Peneda são consensualmente consideradas como áreas montanhosas afetadas pelas glaciações quaternárias, embora outras montanhas, apesar de mais baixas, pareçam evidenciar idênticos efeitos das glaciações. Apresenta-se neste trabalho uma síntese dos conhecimentos atuais e as perspetivas de investigação dos vestígios glaciares nas montanhas do NW de Portugal.