population genetics bio341 mutation - the ultimate source of all genetic variation recombination -...
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Population geneticsBio341
• Mutation - the ultimate source of all genetic variation
• Recombination - shuffles existing alleles
• Selection - different alleles and genotypes have different fitness. Frequencies change with time
• Migration - introduces alleles and genotypes into populations
• Drift - results in the loss of alleles from populations
A population is:
• a group of individuals of the same species from which the next generation is drawn. (Often included is that members of the same population occupy the same locality and ecological niche.)
Consider a population that is:
• Haploid• Asexual (no recombination)• Not subject to any kind of selection
For any pair of individuals, what is the chance of a common ancestor in the generation immediately preceding?
Answer: 1/N
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1 2 33 44 55 6
Individuals
Generations
For any pair of individuals, what is the average time back to the most recent common ancestor?
Answer: N generations
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1 2 33 44 55 6
Individuals
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For any pair of individuals, what is the average number of mutational events separating them?
Answer: 2Nwhere is theRATE of mutation per gene (or per nucleotide) per generation.
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1 2 33 44 55 6
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