Evolution/Adaptations

punctuated equilibrium

Pattern of evolution in which long stable periods are interrupted by brief periods of more rapid change

Gradualism

The theory that evolution occurs slowly but steadily

Evolution

Change in a kind of organism over time; process by which modern organisms have descended from ancient organisms.

Adaptation

A trait that helps an organism survive and reproduce

natural selection

A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.

artifical selection / selective breeding

selective breeding of plants and animals to promote the occurrence of desirable traits in offspring

vestigial structures

remnant of a structure that may have had an important function in a species' ancestors, but has no clear function in the modern species.

homologous structures

Structures in different species that are similar because of common ancestry.

DNA

A complex molecule containing the genetic information that makes up the chromosomes.

Embryology

study of embryos and their development

Variation

differences in physical traits of an individual from the group to which it belongs

Darwin's Theory of Evolution

English natural scientist who formulated a theory of evolution by natural selection (1809-1882)

Lamarck's theory

individuals can acquire traits during their lifetime and pass them onto their offspring

camoflauge

An adaptation that allows an organism to blend in with its environment

mimicry

The resemblance of one species to another species

Biodiversity

the variety of life in the world or in a particular habitat or ecosystem.

ancestor

A relative who lived in the past

geologic record

The division of Earth's history into time periods, grouped into three eons—Archaean, Proterozoic, and Phanerozoic—and further subdivided into eras, periods, and epochs.

fossil record

Chronological collection of life's remains in sedimentary rock layers

geographic isolation

form of reproductive isolation in which two populations are separated physically by geographic barriers such as rivers, mountains, or stretches of water