Microevolution: when a population changes over time Flashcards
What is microevolution?
Gradual change that a population undergoes over many generations as it evolves. Involves a change in phenotypes of the individuals in a population over time.
Phenotypes are determined by…
Alleles an individual has
Evolution can be defined as…
a change in allele frequencies in a population over time.
What is a Gene pool?*
Total alleles of all genes in a population.
What factors can cause evolution?
- Natural selection
- Mutation
- Gene flow
- Genetic drift
- Non-random mating
What is natural selection?
Selects for alleles that give phenotypes that allow an organism to best survive/reproduce in its environment.
What is mutation?
It can be caused by radiations or chemicals in the environment.
What is Gene flow?
Individuals migrate in or out of the population.
Why gene flow can cause evolution?
Because there is new breeding between populations.
What is genetic drift?
The effect of chance events on allele frequencies in a population.
What are the two kinds of genetic drift?
Population bottleneck: when a chance event eliminates many individuals at random from the population in a short period of time.
The founder effect: when a few individuals start a new population in a new area due to some random chance effect.
What is non-random mating?*
When mates are not chosen randomly in a population.
-preference for the same phenotype
-limited mate choice due to isolation
