Species-Area Relation and Self-Similarity in a Biogeographical Model of Speciation and Extinction

We introduce a generic model for the population growth and dispersal of individuals in species with heterogeneous, fluctuating environments. New species originate with a probability inversely proportional to the abundance of the parent species. The model generates an average number of species which depends on the domain area in agreement with the species-area relation for islands. The model also generates self-similar radiations characterized by a power-law distribution for the number of subtaxa with the same parent taxon and a 1yf power spectrum for the time series of extinctions and originations. [S0031-9007(99)08604-4]