The Origin and Evolution of Amazonian Species Diversity

Abstract

We identify key interdisciplinary questions and approaches to understanding the paleogeographic and biotic history of Amazonia. We discuss the importance of comparing evolutionary taxonomic units across groups and considering their particular environmental affinities as a framework for a mechanistic understanding of how the diversity of Amazonia was assembled across space and time. Although lineage diversity of the Amazonian biota is often quite old, current evidence indicates that much of Amazonia’s observed “species-level” diversity, as exemplified by birds, mammals, and butterflies, is young, mostly dating to the Quaternary. Much of the modern Amazonian landscape, including in particular its hydrological and environmental systems, was shaped over the Pliocene and Quaternary (last 5 Ma), yet significant landscape change affecting the evolution of biotas is less than 2 million years old.