Bio94W25_Lesson06_ARV_Blank

Evolutionary Processes

The mechanisms that lead to changes in allele frequencies over time, including natural selection, genetic drift, gene flow, and mutation.

Genetic Drift

Random changes in allele frequencies due to sampling error, often pronounced in small populations.

Founder Effect

A form of genetic drift that occurs when a small group from a larger population establishes a new population, leading to reduced genetic diversity.

Population Bottleneck

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

Gene Flow

The movement of alleles between populations, which can increase or decrease genetic variation.

Mutation

A permanent change in an organism's DNA that introduces new alleles into a population.

Neutral Mutation

A mutation that does not affect the fitness of an organism.

Beneficial Mutation

A mutation that increases the fitness of an organism.

Deleterious Mutation

A mutation that decreases the fitness of an organism.

Allele Frequency

The proportion of a particular allele among all allele copies in a population.

Natural Selection

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

Sampling Error

A statistical error due to a small sample size that may not represent the population accurately.

Directional Selection

A mode of natural selection in which one extreme phenotype is favored over others, causing the allele frequency to shift over time.

Frequency-Dependent Selection

A type of selection that depends on the frequency of a phenotype or genotype in the population.

Fitness

The ability of an organism to survive and reproduce in its environment.

Allele

Different forms of a gene that may produce distinguishable phenotypic effects.