The metaphor of holey adaptive landscapes provides a pictorial representationof the process of speciation as a consequence of genetic divergence. In thismetaphor, biological populations diverge along connected clusters of well-fitgenotypes in a multidimensional adaptive landscape and become reproductivelyisolated species when they come to be on opposite sides of a ``hole'' in theadaptive landscape. No crossing of any adaptive valleys is required. Iformulate and study a series of simple models describing the dynamics ofspeciation on holey adaptive landscapes driven by mutation and random geneticdrift. Unlike most previous models that concentrate only on some stages ofspeciation, the models studied here describe the complete process of speciationfrom initiation until completion. The evolutionary factors included areselection (reproductive isolation), random genetic drift, mutation,recombination, and migration. In these models, pre- and post-matingreproductive isolation is a consequence of cumulative genetic change. I studypossibilities for speciation according to allopatric, parapatric, peripatricand vicariance scenarios. The analytic theory satisfactorily matches results ofindividual-based simulations reported by Gavrilets et al. (1998). It isdemonstrated that rapid speciation including simultaneous emergence of severalnew species is a plausible outcome of the evolutionary dynamics of subdividedpopulations. I consider effects of population size, population subdivision, andlocal adaptation on the dynamics of speciation. I briefly discuss someimplications of the dynamics on holey adaptive landscapes for molecularevolution.
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