Null Hypothesis, HWE, and Speciation

Equilibrium

No change in a population’s allele frequencies over time

To determine if a population is evolving, we must show that it is ______

Not in equilibrium

Hardy-Weinberg Equilibrium

What happens in an entire population when all individuals (and thus possible genotypes) breed

Assumptions of HWE

1. Not evolving (no selection)

2. No mutation

3. No migration (no genetic drift or gene flow)

4. Large population

5. Random mating

Phenotype

Physical expression of genes

Genotype

Genetic information (alleles)

Gene pool

All possible alleles

Calculate genotypic frequencies

Observed / total

Calculate allele frequencies

P = p² + ½ (2pq)

Q = q² + ½ (2pq)

P

Homozygous dominant

Pq

Heterozygous

Q

Homozygous recessive