CH 15 Vocabulary Evolution

Random change in allelic frequencies in a population.

More-primitive characteristic that appeared in common ancestors.

A small population separated from the rest of the pop-interbreeds, produces allelic variations.

Factor that prevents individuals of different species from mating-operates before fertilization

Theory that evolution occurs in gradual steps over time.

Hereditary changes in groups of living organisms over time.

New feature that had not appeared in common ancestors.

Reduced form of a functional structure that indicates shared ancestry.

Same function but different structure that is not inherited from a common ancestor.

Factor that prevents a hybrid zygote from developing or reproducing; occurs after fertilization

Theory that evolution occurs with relatively sudden periods of speciation then stability.

Shift of a population toward an extreme version of a beneficial trait.

Morphological adaptations that allow organisms to blend into their surroundings.

Population divided by a geographic barrier evolves into two + populations unable to interbreed.

Diversification of a species into a number of different species over a short time span.

Allelic frequencies in populations stay the same unless affected by a factor causing change.

Darwin's theory excess reproduction, variations, inheritance, & advantages of specific traits.

Change in the frequency of a trait based on the ability to attract a mate.

Organism's early prebirth stage of development.

Individuals with average traits are removed creating two populations with extreme traits.

Morphological adaptation where 1 species evolves to resemble another for protection, etc.

Most common form of natural selection-organisms with extreme expressions of a trait are removed

Study of the distribution of plants and animals on earth.

Similar structure inherited from a common ancestor.

Measure of a trait's relative contribution to the following generation.

Process in which a large population declines in number and rebounds.

Directed breeding to produce plants and animals with desired traits.

Occurs when a species evolves into a new species in an area without a geographic barrier.