Population genetics describes how genetic variation changes within and between populations over time. These theory pages explain the mathematical models underlying each simulation, with interactive diagrams and links to hands-on experimentation.
Hardy-Weinberg Equilibrium
The foundation of population genetics: genotype frequencies in an ideal population
De FinettiChi-Square Test
Genetic Drift
Random changes in allele frequencies due to finite population size
Pure DriftMarkov ChainHeterozygosity
Natural Selection
How differential fitness shapes allele frequencies over generations
Natural SelectionFrequency-Dependent
Mutation
The ultimate source of genetic variation and its population-level effects
Two-Way MutationIrreversibleNeutral
Gene Flow & Population Structure
Migration between populations and its effects on genetic differentiation
Continent-IslandF-StatisticsWahlund
Linkage Disequilibrium
Non-random association of alleles at different loci
DisequilibriumMagnitude of D
Mating Systems
How non-random mating affects genotype frequencies
Assortative MatingAssortative Matrix