The Past and Future of an Endemism Hotspot

Gabriele Casazza, Ph.D.

DISTAV-Department for the Earth, Environment and Life Sciences, University of Genoa

In general, endemism richness is expected to be high where past climate fluctuations have been mild, buffering lineages against extinction. Understanding the processes that influence the endemic richness is useful for protecting them in the future. An area rich in endemisms are the SW Alps, where rugged topography and the closeness of the sea weakened the effect of climatic fluctuations, minimising the extinction of populations and genotypes. In fact, separation of major clades predates the last glaciation, and the following climatic fluctuations further drove differentiations. Moreover, demographic patterns do not conform to the “Expansion-Contraction” model. However, even if the climate stability probably affected genetic and demographic patterns, endemic richness results from the interaction of dispersal capability with historical factors, suggesting a more complex pattern. Rugged topography and proximity to the sea will likely protect endemics from extinction also in the future. Moreover, the effect of climate change depends on the difference between the current climate in which the species grow and the future one.