Adaptive value

Traits allowing an organism to survive and reproduce in a particular set of conditions.

Related concepts:

Inclusive fitness

A term in evolutionary biology concerning a total measure of various strategies an organism may use to ensure its genetic success, comprising of an individual's personal fitness, that is, propagating its own genes into the next generation, as well as Kin Selection strategies, that is, acting in ways which are likely to increase the reproductive success of its close biological relatives.

Darwinian fitness

The degree to which an organism is successful in its production of viable offspring, that is, its reproductive success, relative to other organisms, hence, the extent to which its genes are represented in subsequent generations.

Reproduction

Any process by which an organism gives rise to or produces a new individual or individuals.

Gene

Physical or material unit of heredity.

Genetic Drift

Where a mutation occurs - a distinct variant of a gene on a molecular level - but the gross expression of the variant, on the level of the whole organism, is of an identical effect to the original form, yet the new mutant form can replace the original in the gene pool even though no selective advantage - beyond that already embodied in the original form - has been conferred. Known as the Neutral Theory of Molecular Genetics.

(see also: the principle of Natural Selection, Darwinism, Evolution, Genetic Recombination, Mutation, Creationism, science, scientific approach, scientific methodology, pseudo-science)