Biology Chapter 23

a change in the allele frequencies of a population.

by recognizing that some species had traits that either appeared in their offspring or didn’t.

A study of the extensive genetic variation within populations as well as quantative characteristics.

A theory of evolution formed in the 1940s that emphasized the importance of populations as the units of evolution, the central role of natural selection as the most important mechanism of evolution and the idea of gradualism to explain how large changes can evolve as an accumulation of small changes occurring over long periods of time.

The total aggregate of genes in a population at any one time consisting of all alleles at all gene loci in all individuals of the population.

The frequencies of alleles and genotypes in a populations gene pool remain constant over the generations unless acted upon by agents other than Mendelian segregation and recombination of alleles.

When a populations gene pool is in a state of equilibrium

P^2 + 2pq + p^2 = 1

To calculate frequencies of alleles in a gene pool if frequencies of genotypes are known or vice versa

1. A very large population size 2. No migration 3. No net mutations 4. Random mating 5. No natural selection.

evolution

a generation to generation change in a populations frequencies of alleles.

natural selection because selection favors the disproportionate propagation of favorable traits.

a change in a populations allele frequencies due to chance

the bottleneck effect and the founder effect