The Mediterranean is a dramatically broken up and complicated region with mountains, valleys, islands and coasts. There’s enormous variation in environment over tiny distances. During Ice Ages these differences translate into a mosaic of variation that allows some areas to retain some of the features of a Mediterranean environment even when the cold and the dryness is widespread. And in these areas, the size perhaps of Sicily or the Peloponnese or the southern coast of Spain, flora and fauna could endure but also speciate and evolve. Over millions of years, this has created one of the richest and most diverse flora that we have anywhere in the world.