Genetic Drift, Gene Pool, & Population Genetics

True

True or False:

Small population sizes are more strongly influenced by random events than large populations

Genetic drift

A rapid movement of allele frequencies

Bottlenecks

An incident reduces the overall number of individuals in a population and only a few survive to produce the next generation

Cheetah and Northern elephant seal

Give 2 species that experienced genetic drift

Founder effect

A small number of individuals disperse and colonize new habitat, founding a new population. Small subsequent population size plays a big role in additional changes to the gene frequencies

Population

A group of organisms of the same species that live together in a particular location

Population Genetics

- The study of genes in a population of organisms

- Genetic basis of evolution

Population

A group od interbreeding individuals located in the same area and separated physically from other populations of the same species

Gene pool

The genotype of a population consisting of all of the alleles present in the population members for all of the genes found in that species

Evolutionary change

This occurs when there is a measurable change in the population's genotype through time

Alteration in the allele frequencies for a single gene

What is the smallest unit of evolutionary change?

Godfrey Harold Hardy & Wilhelm Weinberg

They developed a model expressing the equilibrium etween the allele frequencies for a single gene and the genotype frequencies among population members for that gene as an expansion of the binomial (p+q)^2

1. Mutation must not occur or if it does there must be mutational equilibrium.

2. Migration (immigration or emigration) must not occur in the population.

3. Population size must be large.

4. Survival and reproductive success of population members must be random and independent of their genotypes.

Hardy-Weinberg condition:

Hardy-Weinberg conditions

These are necessary to ensure that gametes, and their alleles, combine randomly to produce new individuals in the next generation