Why is a population a unit of evolution?

Despite the fact that individual populations within the range of the species are relatively isolated, between them there is always an exchange of individuals. This provides a relationship between different populations and, therefore, the integrity of the species. The totality of genes and genotypes of a population is called the gene pool of the population. The collection of gene pools of different populations forms the gene pool of the species. The gene pool of any population is unique, as it reflects morphophysiological characteristics, ensures the fitness of individuals to environmental conditions specific to a given area. Over time, the gene pool of populations changes. Mutation process and migrations of individuals lead to the emergence of carriers of new traits in populations. Such carriers participate in the struggle for existence. Natural selection “rejects” individuals with “unsuccessful” characters (therefore, genotypes), and thereby favors the reproduction of individuals with “successful” characters (therefore, successful genotypes). So, as generations of the gene pool change, the population changes under the influence of natural selection. Therefore, the ratio of different gene pools in a population, that is, its genotypic structure, is changing. This process is an elementary evolutionary event and, under certain conditions, can lead to the formation of new species.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.