The Eco - Geo - Clim model: explaining Madagascar’s endemism

Paleoclimatic oscillations (top left) driving tropical island endemism by producing alternating wet (S1) and dry (S4) conditions (bottom left), with Madagascar's centers of endemism (right panel, green) located between watersheds with headwaters at high altitude and extended riparian forest (right, blue). PAGE 6 4 le cas de sous bassins versants dans lesquels un coulement a t prenne et o la fort et sa faune associe ont pu subsister. 2) Dans certaines parties basses, profitant de spcificit gologiques et gomorphologiques, des milieux exceptionnels ont facilit la conservation, la transformation et l'volution de certaines espces endmiques. Ce processus est dnomm modle Eco -Geo -Clim.