Population Genetics Population Genetics

Marie ČernáMarie Černá

PopulationPopulation

a localized group of individuals belonging to the same species

a species a group of populations whose individuals have the potential to interbreed and produce fertile offspring in nature

Population geneticsPopulation genetics (in the 19(in the 19330s)0s)

• Study of the properties of genes within populations (gene pool)

• The genetic structure of a population is defined by its allele and genotype frequencies

• Microevolution is a generation-to-generation change in a population’s allele or genotype frequencies

Modern synthesisModern synthesis(forged in the 1940s)(forged in the 1940s)

• a comprehensive theory of evolution

• integrates Darwinian selection and Mendelian inheritance

Hardy-Weinberg equilibriumHardy-Weinberg equilibrium• very large population• no migration• no net mutations• random mating• no natural selection

in a population meeting all these conditions - no evolution is occurring

Hardy-Weinberg equilibriumHardy-Weinberg equilibrium

p = frequency of dominant alleleq = frequency of recessive alleleallele frequencies: p + q = 1genotype frequencies:

(p + q)2 = p2 + 2pq + q2 = 1

LiteratureLiterature

Biology, eighth edition,Campbell, Reece

Unit four: Mechanisms of EvolutionChapter 23: The Evolution of PopulationsPages 468 – 486