Biogeographical units matter

Abstract

One of the recurrent themes in historical biogeography relates to the units of analysis, their definition and identification. Although areas of endemism are usually accepted as the standard units of study, other units have been suggested, as well as several methods for identifying them. There is no consensus on which units are best suited for the studies; however, the effect of the units and area schemes on analytical results is acknowledged. Here, I review the literature on biogeographic units, their uses and recommendations, highlighting the relevance of the use of more than one area-classification scheme in empirical studies.