Summary
Mathematical models using selection, mutation, drift and migration to predict allele frequency change.
In depth
Wright-Fisher models simulate drift in finite populations; selection coefficients describe the strength of selection; coalescent theory looks backward to infer ancestry. Mutation-selection balance keeps harmful alleles at low frequency.
Models help predict the effect of selection on allele frequency.
Models combine the four forces: mutation, drift, selection and gene flow. The selection coefficient s measures reduced fitness, and the dominance coefficient h its expression in heterozygotes; with s of 0.01 an allele changes fast in large populations. Effective population size, often much smaller than census size, determines drift.
Neutral theory (Kimura) holds that most molecular variation is neutral, and nearly neutral theory adds slightly harmful variants. Coalescent methods use gene trees to estimate historical population size and divergence times, as in studies of human origins, and methods like PSMC infer past population sizes from a single genome.
Remember: models are simplified and test our understanding by comparing prediction with data.
Frequently asked questions
What is Population Genetics Models?
Mathematical models using selection, mutation, drift and migration to predict allele frequency change.
Which area of biology covers Population Genetics Models, and how advanced is it?
Population Genetics Models is one of the 54 topics in Genetics. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Genetic Drift, Gene Flow, Allele.
Can you give an example of Population Genetics Models?
Heterozygote advantage maintains a stable polymorphism at equilibrium.
What should I learn before Population Genetics Models?
Work through the Beginner topics in Genetics first, such as Heredity, Gene, Allele, then return to Population Genetics Models. Advanced topics assume the Intermediate vocabulary.
What topics are related to Population Genetics Models?
The closest topics to Population Genetics Models are Genetic Drift, Gene Flow, Allele, Heritability. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Population Genetics Models?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Population Genetics Models. To practise the whole of Genetics, use the Genetics quiz.
How is Population Genetics Models different from Genetic Drift?
Population Genetics Models: Mathematical models using selection, mutation, drift and migration to predict allele frequency change. Genetic Drift: Random changes in allele frequency that have strong effects in small populations, including the founder effect and bottleneck. Read both side by side and note what each one explains.
How should I study Population Genetics Models step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Genetic Drift and explain the difference aloud. Finally, take the Genetics quiz and come back to this page for any question you miss.