Sierra Nevada, a Mediterranean Biodiversity Super Hotspot

Abstract

The Sierra Nevada massif is a hotspot nested within a biodiversity hotspot in the Western Mediterranean (the Baetic-Rifian range, divided by the Strait of Gibraltar), which in turn is found within one the hottest spots in the World, the Mediterranean Basin. The geographic, geomorphological, geological and climatic history of Sierra Nevada places it at a unique biogeographical crossroads, which explains the high biodiversity levels found there. Here, we review the available literature on the multiple dimensions of biodiversity in Sierra Nevada in different systematic groups. Thus, we go beyond the classical account of endemism as a form of rarity accounting for biodiversity to consider evolutionary and ecological rarities. We focus on successively finer scales, from floristic and faunistic accounts of diversity to community diversity, and then to populations, including phylogenetic, phylogeographic and population genetics information. We also consider biological interactions—mostly mutualisms—that are a fundamental part of biodiversity due to their key role in maintaining species diversity. Finally, we provide some insight into the fate of this biodiversity given the incidence of global change drivers, which may have particularly pernicious consequences in mountainous ecosystems.