BIO Unit 5 notes

Variation

Differences in the genetics of organisms of the same species.

Selection pressure

Varying survival or reproductive ability of different organisms in a breeding population due to the influence of the environment.

Evolution

The cumulative change of heritable characteristics of a population.

Artificial selection

The breeding of plants and animals to produce desirable traits.

Homologous structures

Similar structures due to common ancestry.

Pentadactyl limb

Having limbs that end in five digits.

Continuous variation

Variation in a species, which is controlled by several genes producing features that cannot be divided into discrete categories (ex: human height).

Adaptive radiation

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

Vestigial structure

A structure in an organism that has lost all or most of its original function in the course of evolution, such as human appendices.

Species

A group of individuals of common ancestry that closely resemble each other and are normally capable of interbreeding to produce fertile offspring.