BIO SCI 1A Lecture Notes - Lecture 9: Allele Frequency, Genotype Frequency, Ultraviolet
24 Feb 2018
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Document Summary
Microevolution: changes in the genetic structure of populations: microevolution (df. ): small evolutionary changes, those that result in allele and genotype frequencies in a population: remember: population (df. ): any group of organisms coexisting at the same time and in the same place and capable of interbreeding with one another. Four causes of changes in genetic structure of populations: natural selection, gene pool (df. California cypress: california cypress groves, environmental similar in all groves, rough, smooth, small and large cones, conclusion: variation among populations due to genetic drift. Population bottleneck: large populations can have allele frequencies changed, can come about through natural or human disaster, most genotypes may not appear in next generation. Northern elephant seals: 1890s population reduced to 20 individuals, breeding population lower than this -- only few males mating, result: no evidence of variation among proteins, effect: headed toward extinction. Cheetahs: causes of decline, effect: infertility because of intense interbreeding.
