The Evolution of Populations

These flashcards cover essential vocabulary related to the evolution of populations, focusing on concepts from population genetics, natural selection, and the principles underlying evolutionary processes.

Population Genetics

The study of genetic variation within populations and involves the examination of allele and genotype frequencies.

Hardy-Weinberg Principle

A principle stating that allele and genotype frequencies in a population remain constant from generation to generation in the absence of evolutionary influences.

Natural Selection

The process where organisms better adapted to their environment tend to survive and produce more offspring.

Genetic Drift

A mechanism of evolution that refers to random changes in allele frequencies in a population.

Founder Effect

A phenomenon where a small group of individuals establishes a new population, leading to reduced genetic diversity and different allele frequencies compared to the original population.

Bottleneck Effect

A sharp reduction in the size of a population due to environmental events or human activities, resulting in a loss of genetic diversity.

Mutation

A change in the DNA sequence of an organism that can contribute to genetic variation.

Phenotype

The observable physical or biochemical characteristics of an organism, as determined by both genetic makeup and environmental influences.

Polymorphism

The occurrence of two or more variations of a particular trait within a population.

Fitness

The ability of an organism to survive and reproduce in its environment, measured by the number of offspring produced.

Adaptive Evolution

Evolution that occurs through natural selection, enhancing traits that improve survival and reproduction.

Stabilizing Selection

A type of natural selection that favors average phenotypes and selects against extreme variations.

Directional Selection

Natural selection that favors phenotypes at one end of the spectrum, leading to a shift in the population's traits.

Diversifying Selection

Natural selection that favors two or more distinct phenotypes, leading to increased genetic variance.

Gene Flow

The transfer of alleles or genes from one population to another, often due to migration.

Heritability

The proportion of observed variation in a trait that can be attributed to inherited genetic factors.

Sexual Selection

A form of natural selection where individuals with certain inherited characteristics are more likely than other individuals to obtain mates.

Frequency-Dependent Selection

Natural selection that depends on the commonness or rarity of a phenotype in a population.