Population genetic basis of the evolutionary change.

Short introduction is given to population genetic treatment of the evolutionary change. The evolutionary change in the population is based upon the appearance (by mutation or immigration) of new genetic information. The proportion of this new information may increase or decrease by selection and/or random processes. The aid of population genetics is to formulate models in order to understand the essence of the evolutionary change. Some simple deterministic and stochastic single-locus models are quoted from elementary population genetic theory.