Four Main Evolutionary Processes:1. Natural Selection(Sexual Selection)Effect on Fitness: IncreasesEffect on Genetic Variation: Increase, Decrease, Maintain2. Genetic DriftEffect on Fitness: RandomEffect on Generic Variation: Decreases3. Gene FlowEffect on Genetic Variation: Increases (in recipient pop)Effect on Fitness: Random4. MutationEffect on fitness: RandomEffect on Genetic Variation: IncreasesGene Flow Contd.Genetic variation: number of different alleles in a populationGene flow:Can introduce new alleles to populationsMakes both populations more genetically similarMutation: change in an individuals DNA sequence that results from copying errors in DNA or environmental factorsTypes of Mutations:Change in nucleotide base can create a new alleleGene Duplication: a source of new GENES- redundant gene can evolve new function **one way that genomes can increase in size**Mutation in regulatory region of DNA (“gene switch” or “gene control”): switches gene on/off or turns it up/downMutation adds new alleles/genes to the populationrandom effect on fitnessincreases genetic variation*Mutation alone does not cause significant evolutionary changeSpeciation: the evolution of two or more distinct species from one ancestral speciesGenetic Isolation: allows the opportunity for independent genetic changesDivergence: populations become more genetically dissimilarPhylogenetic tree: diagram/model that represents the evolutionary history of a group of speciesAllopatric Speciation: geographic isolation (can happen 2 ways)Dispersal: population colonizes new habitatVicariance: new physical barrier splits geographic range of speciesEx. Mnts, rivers, joining/separating land massesSympatric Speciation: niche isolationBIOM 150 1nd Edition Lecture 14Outline of Last Lecture I. Genetic Drift and Gene FlowOutline of Current Lecture II. Four Main Evolutionary ProcessesIII. Gene FlowIV. MutationV. SpeciationCurrent Lecture Four Main Evolutionary Processes: 1. Natural Selection(Sexual Selection) Effect on Fitness: Increases Effect on Genetic Variation: Increase, Decrease, Maintain 2. Genetic Drift Effect on Fitness: Random Effect on Generic Variation: Decreases  3. Gene Flow Effect on Genetic Variation: Increases (in recipient pop) Effect on Fitness: Random 4. Mutation Effect on fitness: Random Effect on Genetic Variation: Increases Gene Flow Contd.These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Genetic variation: number of different alleles in a population- Gene flow: - Can introduce new alleles to populations - Makes both populations more genetically similar Mutation: change in an individuals DNA sequence that results from copying errors in DNA or environmental factors Types of Mutations:- Change in nucleotide base can create a new allele- Gene Duplication: a source of new GENES- redundant gene can evolve new function **one way that genomes can increase in size**- Mutation in regulatory region of DNA (“gene switch” or “gene control”): switches gene on/off or turns it up/down- Mutation adds new alleles/genes to the population- random effect on fitness- increases genetic variation*Mutation alone does not cause significant evolutionary changeSpeciation: the evolution of two or more distinct species from one ancestral speciesGenetic Isolation: allows the opportunity for independent genetic changesDivergence: populations become more genetically dissimilar Phylogenetic tree: diagram/model that represents the evolutionary history of a group of speciesAllopatric Speciation: geographic isolation (can happen 2 ways)- Dispersal: population colonizes new habitat- Vicariance: new physical barrier splits geographic range of specieso Ex. Mnts, rivers, joining/separating land massesSympatric Speciation: niche