bio ch22 key terms

The principle stating that mechanisms of change are constant over time. See catastrophism.

inherited characteristic of an organism that enhances its survival and reproduction in specific enviroments

The evolution of similar features in independent evolutionary lineages

The study of the past and present distribution of species.

A branching diagram that reflects a hypothesis about evolutionary relationships among groups of organisms

(strah'-tum)(plural,strata) A rock layer formed when new layers of sediment cover older ones and compress them.

(ho⁻-mol'-uh-je⁻⁾ Similarity in characteristics resulting from a shared ancestry

Having characteristics that are similar because of convergent evolution, not homology

The slow movement of the continental plates across Earth's surface

Descent with modification; the idea that living species are descendants of ancestral species that were different from the present-day ones; also defined more narrowly as the change in the genetic composition of a population from generation to generation

A structure of marginal, if any, importance to an organism. Vestigial structures are historical remnants of structures that had important functions in ancestors

A preserved remnant or impression of an organism that lived in the past

(pan-je'-uh) The supercontinent that formed near the end of the Paleozoic era, when plate movements brought all the landmasses of Earth together

A process in which organisms with certain inherited characteristics are more likely to survive and reproduce than are organisms with other characteristics.

Structures in different species that are similar because of common ancestry

(pa'-le-un-tol'-o-je) The scientific study of fossils

(en-dem'-ik) Referring to a species that is confined to a specific, relatively small geographic area.

(kuh-tas'-truh-fiz'-um) The principle that events in the past occurred suddenly and were caused by different mechanisms than those operating today. See uniformitarianism

The selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits