Evolution

adaptation

A characteristic that improves an individual's ability to survive and reproduce in a particular environment

camouflage

A structural adaptation that enables an organism to blend in with its environment

fitness

Ability of an organism to survive and reproduce in its environment

comparative embryology

Among different species, there are similarities in embryo appearance and anatomy. This concept supports the theory of evolution.

homologous structure

Body parts that are structurally similar in related species

analogous structure

Body parts that share a common function, but not structure

evolution

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

genetic drift

Changes in the gene pool of a small population due to chance

comparative biochemistry

DNA is similar in species that share a common ancestor

Charles Darwin

English naturalist and scientist whose theory of evolution through natural selection was first published in 'On The Origin of the Species" in 1859 after a trip around the world on the HMS Beagle.

speciation

Evolutionary process in which new species arise.

mimicry

Gaining protection by looking and acting like a different species

bottleneck

Genetic drift resulting from the reduction of a population, such that the surviving population is no longer genetically representative of the original population.

founder effect

Genetic drift that occurs after a small number of individuals colonize a new area

biogeography

Geographic distribution of species meaning animals are closer together geographically are more alike than those separated

sexual selection

Mode of natural selection in which some individuals out reproduce other because they are better at securing mates

disruptive selection

Natural selection in which individuals on both extremes of a phenotypic range survive or reproduce more successfully than do individuals with intermediate phenotypes.

directional selection

Natural selection that favors individuals at one end of the phenotypic range.

stabilizing selection

Natural selection that favors intermediate variants by acting against extreme phenotypes.

derived trait

New feature that had not appeared in common ancestors

natural selection

Process by which individuals that are better suited to their environment survive and reproduce most successfully

artificial selection

Selection by humans for breeding of useful traits from the natural variation among different organisms

ancestral trait

more-primitive characteristic that appeared in common ancestors

vestigial structure

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