Biogeography deals with the distribution patterns of species and communities, and their causal relationships with factors such as climate, soil and evolutionary history (Humboldt, 1805; Lomolino. 2006). Specific topics addressed by biogeographers include the sizes of geographical ranges and their spatial placement, the way individual species attain their distribution ranges (dispersal, extinction and vicariance), the distribution of species numbers (alpha diversity), changes in species composition (beta diversity) and the spatial distribution of species traits (macroecology).
