 Island biogeography concerns the distribution and abundances of species on islands. One of the fundamental patterns the biologists have attempted to explain is the species-area effect. That is, why do larger islands support more species than smaller ones? It seems that as the area of an island increases, so does species richness. The species-area effect is the product of the area effect namely that more species are found on larger islands rather than smaller, and the distance effect namely that islands closer to the mainland have more species than those that are further. E. O. Wilson and Robert H. MacArthur provided one of the famous potential explanations of the species area effect. They did so through their equilibrium model of island biogeography (MacArthur &amp; Wilson 1963, 1967). They began with several assumptions. First, species richness on an island has a stable equilibrium. Second, the stable equilibrium is due to the immigration rate from the mainland to the island and the extinction rate on the island. Third, the distance of the island from the mainland by itself determines the rate of immigration. Fourth, the extinction rate is determined solely by the island’s size. Fifth, the stable equilibrium is a dynamic one. The number of species are the island is constant, but the composition of species on the island changes. This rate of change is the species turnover rate.