Mechanisms of Evolution and Shaping Evolutionary Theory

The flashcards cover vocabulary relating to evolutionary theory and mechanisms of evolution, including concepts in population genetics, selection mechanisms, and types of speciation.

Population Genetics

The study of genetic variation within populations and involves the examination of allele frequency and the effects of evolution.

Gene Pool

All the genes available to a particular population.

Hardy-Weinberg Principle

A principle that describes the conditions under which allele frequencies in a population remain constant from generation to generation.

Hardy-Weinberg Equilibrium

The condition where genetic equilibrium is achieved, meaning there are no changes in allele frequencies over time.

Fitness

The relative number of surviving offspring an organism produces, reflecting the success of its genotype.

Genetic Drift

A change in the gene pool of a population due to chance events.

Founder Effect

A phenomenon in which a small group from a larger population establishes a new population, possibly leading to reduced genetic variation.

Population Bottleneck

A sharp reduction in the size of a population that results in a loss of genetic diversity.

Natural Selection

The process where organisms with advantageous traits have higher reproductive success, changing the gene pool.

Stabilizing Selection

A type of natural selection that favors intermediate variants and acts against extreme phenotypes.

Directional Selection

A type of natural selection that favors one extreme phenotype over other phenotypes.

Disruptive Selection

A form of natural selection that favors extreme phenotypes at both ends of the spectrum over intermediate phenotypes.

Sexual Selection

A mode of natural selection in which certain traits increase mating success.

Prezygotic Isolation Mechanisms

Factors that prevent mating or fertilization between species before a zygote is formed.

Postzygotic Isolation Mechanisms

Factors that prevent the hybrid offspring from developing into a viable adult or breeding as adults.

Allopatric Speciation

The formation of new species in populations that are geographically isolated from one another.

Sympatric Speciation

The process of speciation occurring when two groups of the same species live in the same geographic location but evolve differently.

Adaptive Radiation

The diversification of a group of organisms into forms filling different ecological niches.

Coevolution

The process by which two or more species evolve in response to each other.

Convergent Evolution

The independent evolution of similar features in species of different lineages, often due to similar environmental pressures.

Divergent Evolution

The accumulation of differences between closely related populations or species, leading to speciation.

Punctuated Equilibrium

A theory that proposes that evolution occurs in rapid bursts followed by periods of stability.

Modern Synthetic Theory of Evolution

A theory merging Darwin’s theory of natural selection with Mendelian genetics to explain how evolution occurs.