PSYCH 3F03 Lecture Notes - Lecture 7: Genetic Drift, Allele Frequency, Gene Flow
Document Summary
Define dispersal and gene flow and understand their effects on evolution. Define genetic drift and learn its three causes. Define three species concepts and know their pros and cons. Evolution: a change in the frequency of an allele or genotype in a population over time. There are 5 mechanisms of evolution: natural selection, sexual selection, mutations, gene flow (migration/dispersal, genetic drift. Dispersal/migration: the physical movement of individuals from one population to another. Gene flow: the movement of alleles from one population to other. So, therefore dispersal = gene flow, if the individuals form the dispersing population mate with the new population. The physical dispersal might be some individuals moving from one population to the other. The process of gene flow = looking at composition of genes in the next generation of population b after individuals mate with the new individuals. However, in small populations with low genetic variation, gene flow can influence the strength of selection.
