MacArthur-Wilson Island Biogeography TheoryAssume all species have an equal dispersal ability and risk of extinctionAssume no interaction between species on an island Parameters Scaling FactorsSpecies pool on mainland P 0 For distance (f)Area of Island A 0 For area (m)Distance from mainland D 0Colonization probability c 0Extinction probability q 0 Equilibrium Values Spp.richness Immigration, Extinction, and species richness Immigration rateFract.of pool Spp. Richness Immigration Extinction Extinction rate 0 0 #DIV/0! #DIV/0! 0.1 0 #DIV/0! #DIV/0! 0.2 0 #DIV/0! #DIV/0! 0.3 0 #DIV/0! #DIV/0! 0.4 0 #DIV/0! #DIV/0! 0.5 0 #DIV/0! #DIV/0! 0.6 0 #DIV/0! #DIV/0! 0.7 0 #DIV/0! #DIV/0! 0.8 0 #DIV/0! #DIV/0! 0.9 0 #DIV/0! #DIV/0! 1 0 #DIV/0! #DIV/0! 1 0.9 0.8 0.7 0.6 Spp. Richness 0.5 Immigration 0.4 Extinction 0.3 0.2 0.1 0 Row 14 Row 15 Row 16 Row 17 Row 18 Row 19 Row 20 Row 21 Row 22 Row 23 Row 24Graph 1. Immigration rate, Extinction Rate and the Equilibrium Point