Population genetics terms

Population Genetics

the study of genetic variation in populations and how allele frequencies change over time.

Population

A group of individuals of the same species capable of interbreeding. Example: Lions in Serengeti National Park.

Gene Pool

The total collection of genes and alleles in a population. Example: Red and white flower colour alleles.

Allele Frequency

The proportion of a specific allele in a population. Example: Brown-eye allele 60%, blue eye allele 40%.

Genotype Frequency

The proportion of individuals with a specific genotype. Example: BB 25%, Bb 50%, bb 25%.

Natural Selection

Individuals with beneficial traits survive and reproduce more successfully. These advantageous alleles become more common over generations.

Genetic Drift

Random changes in allele frequencies, especially in small populations.

Founder Effect

Occurs when a small group separates from a larger population and forms a new population. The new population may have reduced genetic variation.

Bottleneck Effect

Population reduction leads to low diversity. Happens when a population is drastically reduced by disease, disaster, or human activity. Genetic diversity decreases because only a few individuals survive.

Gene Flow

Movement of genes between populations through migration or interbreeding. Increases genetic diversity within populations.

Mutation

A mutation is an accidental permanent change in DNA that creates new genetic variation.

Migration

the movement of individuals into or out of a population, which results in the introduction of new alleles and changes the allele frequencies in the gene pool.