Opposite trends in the genus Monsonia (Geraniaceae): specialization in the African deserts and range expansions throughout eastern Africa.

摘要: The African Austro-temperate Flora stands out by its important species richness. A distinctive element of this flora is Monsonia (Geraniaceae), mostly found in the Namib-Karoo but also Natal-Drakensberg, Somalian Zambezian and Saharo-Arabian regions. Here, we reconstruct evolution biogeographic history based on nuclear plastid markers, examine role morphological niche diversification using distribution modeling macroevolutionary models. Our results indicate that first diversified Early Miocene c.21 Ma, coinciding with start desertification southwestern Africa. An occurred c. 4–6 Ma, after a general cooling trend western South Africa rising Eastern Mountains. resulting two main lineages are constituted by: (1) succulents, (2) herbs Natal-Drakensberg plus three further colonised steppes north eastern highest diversity coastal belt, within mosaic-like habitat structure. Diversification was likely driven biome shifts key innovations such as water-storing succulent stems anemochorous fruits. In contrast, unlike other arid-adapted taxa, all share C3 metabolism.