parapatric speciation A type of speciation in which there is free exchange of genes between two populations of organisms living in directly adjacent but environmentally different habitats. Although individuals from the two populations can interbreed, the offspring will not be very successful in either habitat, therefore natural selection tends to promote any mechanisms that decrease the number of crosses between such populations.

parapatric speciation A speciation that occurs regardless of minor gene flow between demes. In many species selective pressures are sufficiently strong on the whole to prevent homogenization of the immigrant genes by interbreeding.

parapatric speciation Speciation that occurs regardless of minor gene flow between demes. In many species selective pressures are sufficiently strong on the whole to prevent homogenization of the immigrant genes by interbreeding.

parapatric speciation Speciation that occurs regardless of minor gene flow between demes. In many species selective pressures are sufficiently strong on the whole to prevent homogenization of the immigrant genes by interbreeding.