Patterns of within species diversity Flashcards
Polymorphism definition
Differences between individuals of the same species
Divergence definition
Differences between individuas of different species
How is the starting frequency of new mutations calculated by
1/ 2(N)
N: population of diploid individuals
Who proposed the neutral theory
Mootoo Kimura
What does the neutral theory hypothesise
That the fate of most mutations contributing to molecular is determined by drift rather than selection
Assumptions of the neutral theory
The mutations are either neutral or weakly selected
What does the theory allow for
Deleterious mutations to be subject to purifying selection and beneficial mutations to be subject to positive selection
How do we measure DNA sequence variation
SNPS and nucleotide diversity
What is nucleotide diversity equation
π = Ndiff / (Npc x L)
What does the Wright-fisher model do
It makes testable predictions about patterns of polymorphism and divergence
What are the assumptions of the Wright-Fisher model
Random mating, no selective differences among the genotypes at the locus, new individuals are formed by sampling at random with replacement of gametes produced by individuals
Whats the Wright-fisher model equation
E(Pi) = 4NeU
Whats the importance of the Wright Fisher model
Helps us interpret data
How diversity is related to effective population size and mutation rate
What are commonly used neutral markers
Synonymous polymorphisms
Silent polymorphisms
