More individuals are born than can survive and was called "the struggle for existence" by Charles Darwin.

The theorist who proposed that evolution occurs through a process called natural selection.

A random change in allele frequency due to a chance occurrence.

When a population that is not evolving when the allele frequency within a population stays the same over many generations.

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

Variation among inherited traits caused by mutations, genetic recombination, and lateral gene transfer.

The process by which organisms with variations more suited to their environment survive and reproduce more than others.

A change in allele frequency following a dramatic reduction in the size of a population, often due to natural disasters such as storms, floods, and fires.

For this to occur, the following five conditions must be met: Large Population Size, Random Mating, No Mutations, No Gene Flow, No Natural Selection.

A mode of selection in which a selective force pushes a population toward the average, median trait.

The difference in rates of survival and reproduction across organisms within their environment.

What natural selection acts upon.

A change in allele frequency when individuals colonize new habitats.

This variable represents the frequency of individuals with the homozygous dominant genotype.

A mode of selection that selects against the average, median trait.

An individual's ability to survive and reproduce within their environment.

Any heritable characteristic that increases an organism's ability to survive and reproduce.

An evolutionary mechanism besides genetic drift that selects individuals in a non-random way.

This variable represents the frequency of recessive alleles within a population.

Non-random mating occurs when an individual chooses a mate based on the traits that are considered to be preferable.

Overproduction, natural heritable variation, and variable fitness.

A permanent change in the nucleotide sequence of one or more genes on a chromosome.

The population that is most negatively affected by genetic drift.

The phenotype that you always start with when working with the Hardy-Weinberg Equilibrium.

When individuals leave a population it leads to a reduction of genetic diversity and allele frequencies within a population.