Late Cretaceous

As with the Early Cretaceous, the past two decades have witnessed a remarkable improvement in the record of Late Cretaceous mammals. Specimens or faunas are now known from most major landmasses, Australia and Africa being the most notable and most unfortunate exceptions. Advances in knowledge have been particularly welcome from the pre-Campanian, or early Late Cretaceous, part of the record. Twenty years ago only two known occurrences —both consisting of practically indeterminate specimens from North America—fell within this time interval (Clemens et al., 1979). Significant early Late Cretaceous specimens and faunas are now known from both Asia and North America.

Eutherians (and, in North America, marsupials) and multituberculates underwent diversification on the northern continents. Late Cretaceous records now available from Western and Central Europe suggest some degree of endemicity during this epoch (Radulescu and Samson, 1997; Gheerbrant and Astibia, 1999). The existing pre-Maastrichtian record for South America lacks boreo-sphenidan mammals, which apparently did not arrive there until the end of the Cretaceous. Instead, endemic groups or derived members of taxa more typical of the Jurassic are present (Bonaparte, 1990).

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