unit 3 mechanisms of evolution vocab

Adaptation

A trait the increases an organisms ability to survive and reproduce in a particular enviornment

Allele frequency

The proportion of a specific allele among all alleles of a gene in a population

Behavioral isolation

A type of reproductive isolation in which two populations develop differences in courtship or mating behaviors that prevent inbreeding

Bottleneck effect

A sharp reduction in the size of a population due to environmental events or disasters, leading to a loss in genetic variation

Directional selection

Natural selection in which individuals at one extreme of a trait have higher fitness than those in the middle or the other extreme

Diversifying/disruptive selection

Natural selection in which individuals at both extremes of a trait have higher fitness than individuals with intermediate traits

Emigration

The movement of individuals out of a population, which can change allele frequencies

Evolution

The change in allele frequencies in a population over time

Extinction

The complete disappearance of a species from Earth

Founder's effect

When a small group of individuals established a new population, and the gene pool reflects the genetic makeup of founders

Genetic recombination

The exchange of genetic material between chromosomes during meiosis, creating new combinations of alleles in offspring

Geographic isolation

Physical separations of populations by barriers such as mountains, rivers, or distances, preventing gene flow

Immigration

The movement of individuals into a population, which can introduce new alleles

Migrations

The movement of individuals or populations from one location to another, affecting gene flow

Mutations

A change in the nucleotide sequences of DNA that can introduce new genetic information

Non-Random mating

When individuals chose mates based on specific traits rather than mating randomly, affecting alleles frequencies

Population

A group of individuals of the same species living in the same area at the same time

Reproductive isolation

Mechanisms that prevent populations from interbreeding and producing fertile offspring

Stabilizing selection

Natural selection in which individuals with intermediate traits have higher fitness than these at either extremes

Temporal isolation

A type of reproductive isolation in which populations reproduce at different times or seasons

Variation

Differences in traits among individuals of a population which can be genetic or environmental

Differential reproductive success

A measure of fitness that compares reproductive success between groups of individuals within a population