- Microevolution is the generation to generation change in the allele frequencies of a population.
- Causes of microevolution include:
- Genetic Drift
- In small gene pool it's easy to lose alleles.
- Bottleneck effect - a reduction in population reduces alleles for population rebound.
- Founders effect - a colony is restricted to the allele frequency of its founder(s).
- Natural selection - leads to better adaptations.
- modes of selection
- stabilizing - birth weight
- directional - Geospiza animation
- disruptive - Pseudacraea eurytus, Pyrenestes ostrinus
- ecological selection
- reproductive isolation
- reproductive barriers
- sexual selection
- Mutation -
- Gene flow - migration and recruitment.
- Nonrandom mating -
single gene mutation