Genetic Drift

gene stuff

genetic drift

small-scale changes in allele frequencies within a population from one generation to the next

gene pool

all alleles present in a population

genetic drift

a random change in allele frequencies, often having the strongest effects in small populations

bottleneck effect

occurs when a population size is dramatically reduced due to a disaster, reducing genetic variation

founders effect

when a new population is established by a small number of individuals, only carrying part of the genetic diversity (ex: Amish)

gene flow

introduces new alleles into a population by individuals moving between populations

mutation

the ultimate source of all genetic variation

sexual reproduction

increases genetic variation through new combinations of alleles