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The wings of flightless birds, like the ostrich, are an example of this.
Vestigial Structures
Rapid evolutionary change.
When two organisms, such as predator and prey, evolve in response to one another.
Coevolution
Evolution that results in the formation of homologous structures.
Divergent evolution
Study of body structures to provide evidence of evolution.
Anatomy
Study of nucleic acids and proteins to show evolutionary relationships.
Biochemistry
Biological change over time that causes descendants to be different from their ancestors.
Descent with Mod.
When traits that favor reproduction, even though they may decrease an organism's ability to survive, become more common over time.
Sexual Selection
Evolution that results in the formation of analogous structures.
Convergent evolution
Remnants of organisms such as imprints, bones, and feces.
Fossil
Migration
Gene Flow
Principle of natural selection that explains how beneficial traits should become more common over time, causing a change in allelic frequencies.
Evolution
When allelic frequencies are stable and unchanging, therefore evolution in not occurring.
Genetic equilibrium
All of the genes available in a population.
Gene pool
Slow elimination of species caused by small environmental changes over extended periods of time.
Gradual extinction
A physical trait that increases an organism's ability to survive in its environment.
Body structures that are similar in orientation, but completely different in function due to organisms living in different environments.
Homologous Structures
When isolation, such as geographically, causes two populations of organisms to become so different that they can no longer reproduce with each other and create viable offspring.
Speciation
Slow change in allele frequencies over long periods of time.
Gradualism
Similar body structures, such as fins, due to organisms living in the same environment, not same ancestry.
Analogous structures
Sudden elimination of a species due to a catastrophic event.
Mass extinction
Study of embryological development in vertebrates that has led to support the theory of common ancestry among vertebrates.
Embryology
The study of prehistoric life that allows scientists to make connections between current and extinct species.
Paleontology
Organisms with traits that make them better adapted to their environment will live longer and reproduce more than organisms less adapted to the environment.
Natural Selection
Study of the physical distribution of plants and animals.
Biogeography