gsdf

Microevolution

Genetic change occurring within natural populations, involving changes in allele frequencies over generations.

Polymorphism

Different allelic forms of a gene in a population, such as orange vs. black fox squirrels.

Allele

One of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome.

Macroevolution

Evolution on a grand scale, including the origin of new structures, evolutionary trends, adaptive radiation, and mass extinction.

Adaptive Radiation

A process where a single species rapidly diversifies into many new forms.

Genetic Variation

Variation resulting from unique combinations of alleles through processes like crossing over, independent assortment, fertilization, and mutations.

Hardy-Weinberg Principle

A principle stating that genotype proportions in a population remain constant under certain conditions, such as no mutation or selection.

Genetic Drift

Change in allele frequency due to chance, particularly affecting small populations and uncommon alleles.

Gene Flow

The introduction of new traits into an existing gene pool, changing allele frequencies.

Natural Selection

Differential reproductive and survival rates in populations that cause allele frequencies to differ among populations.

Speciation

The lineage-splitting event that forms two new species from an ancestral species.

Biological Species Concept

Defines species as groups of organisms that can interbreed in nature to produce viable and fertile offspring.

Reproductive Isolation

Mechanisms that prevent successful reproduction between different species, occurring prezygotically or postzygotically.

Morphospecies Concept

Defines species based on physical traits, assuming members of the same species look similar.

Phylogenetic Species Concept

Defines species as groups of organisms sharing a unique evolutionary history and ancestry based on genetic data.

Sympatric Speciation

Differentiation of populations within a common geographical area into distinct species.

Allopatric Speciation

Differentiation of geographically isolated populations into distinct species.

Adaptive Radiation

Diversification of a group of organisms into forms filling different ecological niches.

Character Displacement

Maximization of different traits among co-occurring similar species to reduce competition.

Gradualism

The accumulation of small changes over time in the process of evolution.

Punctuated Equilibrium

Long periods of stasis in evolution followed by rapid change.

Biogeography

The study of the geographic distribution of species, revealing patterns of similar adaptations in different areas.

Convergent Evolution

The evolution of similar forms in different isolated areas due to similar selective pressures.