Population Genetics and Evolution

These flashcards cover essential concepts in population genetics and mechanisms of evolution, as discussed in the lecture notes.

Microevolution

Evolution from a population or genetic perspective, focusing on changes in allele frequencies.

Allele Frequency

The relative frequency of an allele at a genetic locus in a population.

Genotype Frequency

The proportion of a specific genotype among all individuals in a population.

Natural Selection

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

Genetic Drift

Random changes in allele frequencies in a population, significant in small populations.

Gene Flow

The transfer of genetic variation from one population to another.

Hardy-Weinberg Equilibrium

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

Directional Selection

A mode of natural selection that favors a specific phenotype, leading to a shift in allele frequencies.

Stabilizing Selection

A mode of natural selection that favors intermediate phenotypes, reducing variation.

Disruptive Selection

A mode of natural selection that favors extreme phenotypes over intermediate ones, potentially leading to speciation.

Bottleneck Effect

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

Incomplete Dominance

A genetic scenario in which one allele does not completely dominate another, resulting in a phenotype that is a blend of both alleles.

Heterozygote Advantage

A situation in which heterozygous individuals have a fitness advantage over homozygous individuals, promoting genetic diversity.

Frequency-Dependent Selection

Selection that favors phenotypes depending on their frequency in a population, which can maintain multiple alleles.

Equilibrium Genotype Frequencies

The expected frequencies of genotypes in a population when it is not evolving, derived from allele frequencies.

Mutation

A change in the DNA sequence that can lead to genetic variability and may affect allele frequency.

Population Genetics

The study of the distribution and change in frequency of alleles within populations.

Phenotype

The observable traits or characteristics of an organism resulting from the interaction of its genotype and environment.