BIO120H1 Lecture Notes - Lecture 7: Genetic Drift, Phenotypic Plasticity, Gene Flow

• School: UTSG
• Department: Biology
• Course: BIO120H1
• Professor: Frederickson M. Wright S.

Document Summary

Bio120 lecture 7: population structure, gene flow & genetic. Population structure, gene flow & genetic drift: population differentiation. Population group of individuals of a single species occupying a given area at the same time. Migration the movement of individuals from one population to another. Gene flow the movement of genes from one population to another. Key questions for evolutionary studies of variation within populations. Polymorphic neutral genetic variation used to study population processes affecting genetic diversity. Frequency of heterozygotes = an estimate of gene flow. Most gene flow occurs over a short distance, but a small amount occurs as far as 1km. Stochastic (unpredictable or random) evolutionary forces: mutation, recombination, genetic drift. Deterministic (predictable or non-random) evolutionary force: natural selection. Stochastic processes resulting in a loss of diversity. Genetic drift stochastic changes in allele frequency due to random variation in fecundity and mortality; most important when populations are small.