Speciation : Population Genetics Flashcards
Founder Effect? impact on genetic variation?
When a small group of individuals emigrate from a population or become geographically isolated from their original population (decreased genetic variation)
Bottleneck Effect?
Sudden dramatic reduction in the size of a population (environmental/human activity) resulting in a significant reduction in a gene pool and genetic variation between individuals in a population
(large impact on small populations –> risk of extinction)
What is Genetic flow?
When alleles move from one population to another via an individual migrating in/out of a population.
What is Genetic Variation?
The difference in alleles in the gene pool of a population.
What is Natural Selection?
When populations of organisms are subjected to selection pressures and individuals with favourable alleles that make them best suited to their environment are more likely to survive and reproduce.
What is Genetic Drift?
Random changes in the frequency of alleles within a population over time due to chance rather than natural selection.
What is Sexual Selection?
A type of natural selection where members of one sex choose mates of the opposite sex based on phenotypic features.
