Genetic revolutions in relation to speciation phenomena: the founding of new populations.

Examines the mode of origin of a population that may be genetically competent to continue, giving rise to a new species in immediately succeeding generations, particularly addressing the idea that a new species may be formed allopatrically following a very simple type of population subdivision - the establishment of a new (daughter) population from one or a few founder individuals. The authors argue that, under some circumstances, the founder event may set the stage for speciation by altering genetic conditions in the gene pool. In the generations immediately following the founder event, genetic change that is largely recombinational may be profound enough to result in the emergence of a descendant population which is recognisable as a new biological species. Support for these ideas is drawn from aspects of both continental and oceanic island biogeography, and discussion focuses on coadapted gene complexes. Three models are provided of founder-induced speciation models, and implications are shown for marcoevolution. -P.J.Jarvis