Reorganization of Late Quaternary Mammal Faunas and Causes of Mass Extinction [Réorganisation des faunes du quaternaire final et causes de l'extinction de masse].

Résumé

Research on end-Pleistocene mass extinction of large-bodied North American mammals has focused on relatively short time scales like that of the extinction episode itself, and on relatively minor ecological phenomena like the geographic distributions of individual species. Here, I discuss two general lines of research intended to correct these problems. The first involves my database of Cenozoic North American mammalian paleofaunas, which provides a backdrop for understanding Pleistocene extinction rates. The second project involves the FAUNMAP database, graciously made available on-line by the FAUNMAP Working Group. The results of these analyses have interesting ecological implications. The biogeographic coherence of mammalian faunas challenges climate- or vegetation-driven mechanisms for mass extinction. If small mammal communities survived unscathed, how could environmental change have suddenly and almost totally destroyed the continents large mammal communities? Together with the intense, rapid, and selective nature of the extinction in comparison to any other event in the Cenozoic, the results add to the already weighty evidence against non-anthropogenic models for mass extinction.