p
Frequency of dominant or normal allele (A)
q
Frequency of recessive or mutant allele (a)
p^2, 2pq, q^2
Frequency of AA, Aa and aa
W
Fitness of a genotype
s
Selection coefficient
How much less fit a genotype is compared to the best one.
h
Dominance coefficient
h=0 allele a is completely recessive
h=1 allele a is completely dominant
μ
mutation rate from A to a per generation
nu (v)
back-mutation rate a to A
Mutation-selection balance formulas
For haploid or dominant alleles:
For recessive allele:
General diploid case:
q = μ/s
q= sqrt(μ/s)
q= μ/hs (if h>0)
H[t]
Expected heterozygosity (two different alleles) at generation “t”
p-hat
q-hat
Equilibrium frequencies
Phylogenetic species concept
A species is the smallest group of organisms that share a common ancestor and can be distinguished from other groups by unique traits.
Defines species by their evolutionary history and unique traits.
General Lineage species concept
Species are evolving populations that became distinct over time.
Biological Species Concept
A species is a group of organisms that can interbreed with each other, producing fertile offspring.
Uniformitarianism
Charles Lyell
If a process was working in the past it will still be working.
How did Darwin view species?
Arbitrary groups of individuals that looked alike.