Population Genetics 1

Chi-Square Goodness-of-Fit-Test

Statistical test used to evaluate how well a set of observed values fits the expected values. The probability associated with a calculated chi-square value is the probability that the difference between the observed and the expected values is due to chance.

Population Genetics

Study of the genetic composition of population and how that composition changes geographically and with the passage of time.

Mendelian Population

A group of interbreeding, sexually reproducing individuals that have a common set of genes

Gene Pool

Set of all genes in a population

Genetic Variation

A measure of the genetic differences that exist within a population.

Natural Selection

A fundamental mechanism of evolution where organisms better adapted to their environment tend to survive and produce more offspring. This process acts on heritable phenotypic variations - such as colour or size - Causing advantageous traits to become more common over generations. It is driven by the differential survival and reproduction of individuals.

Genetic Drift

Change in allelic frequencies due to a sampling error. Unpredictable, chance fluctuations in allele frequency due to random sampling as opposed to natural selection.

Inbreeding

A form of nonrandom mating; preferential mating between related individuals.

Frequency

A proportion or percentage, usually expressed as a decimal fraction

Genotypic Frequency

Proportion of a particular genotype within a population

Allelic Frequency

Proportion of a particular allele within a population.

Hardy-Weinberg Law

Principle of population genetics stating that is a population is large; randomly mating; and not affected by mutation, migration, or natural selection, then allelic frequencies of a population do not change and the genotypic frequencies stabilize after one generation in the populations p² (the frequency of AA), 2pq (frequency of Aa), and q² (frequency of aa), where p equals the frequency of allele A and q equals the frequency of allele a.

Hardy-Weinberg Equilibrium

Frequencies of genotypes when the conditions of the Hardy-Weinberg law are met.