Influence of individuals natural selection by fertility on scenarios of populations with simple age structure development

The paper studies the model of evolution for a two-stage population with birth rate limitation, under the influence of natural selection regulating individual fertility. The model analytical and numerical research has been carried out. With a reduced reproductive potential of heterozygotes, the model is shown to reveal multistability when, depending on the initial values of allele frequencies, stable polymorphism can be realized along with the «bistability trap».