title: Modeling of selection processes with age-dependent birth and death rates.
abstract: Two simple models for the competition and selection in age-dependent populations are developed and analyzed mathematically. Following Eigen, competition is introduced by the condition of constant overall-number of the population. In the first model this condition is satisfied by regulation of a dilution flux and in the second case by regulation of a food density. The calculation of maximal fitness is given explicitly for both situations. It is shown that fitness depends in a complicated way on the age-dependence of the birth and death rates. Therefore species have to develop special aging strategies in order to survive in a population under selection pressure. In general, early reproduction is of advantage and increases fitness.
mesh_terms: D000367:Age Factors; D001723:Birth Rate; D005828:Genetics, Population; D008962:Models, Theoretical; D009026:Mortality; D012641:Selection, Genetic