 | Term | Definition |
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Macroevolution |
Large scale modifications that occur over long time periods and produce new species |
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Relative Dating |
A procedure for comparing the amount of a radioactive isotope and its decay product to determine the age of a geologic specimen |
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Mass Extinction |
One of a brief period of time during which large numbers of species disappeared |
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Homologous |
Similar feature originated in a shared ancestor |
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Vestigial Structure |
Referring to the functionless structure that was functional in an ancestral species |
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Adaptation |
An inherited trait that increases an organisms chance of survival in a particular environment |
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Survival of the Fittest |
The individuals capable of producing the most viable offspring in a population |
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Natural Selection |
The process by which organims with favorable variations reproduce at higher rates than those without such variations |
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Adaptive Radiation |
An evolutionary pattern in which many species evolve from a single ancestral species |
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Disruptive Selection |
A type of natural selection in which individuals with two extreme forms of a trait have an advantage |
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Directional Selection |
Individuals that display a more EXTREME form of a trait have greater fitness |
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Stabilizing Selection |
A type of natural selection in which the average form of a trait causes an organism to have an advantage in reproduction |
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Relative Frequency |
The abundance of one form of a gene or trait compared to an alternative form of the same gene or trait |
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Genetic Drift |
A shift of allele frequencies in a population due to random chance |
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Hardy-Weinberg Principle |
The stability of gene frequencies across generations |
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Gene Equilibrium |
Alternate forms of a trait have equal frequencies |
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Reproductive Isolation |
The inability of formerly interbreeding organisms to produce viable offspring |
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Analogous |
Similar appearance and function but different ancestral origin |
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Speciation |
The formation of a new species |
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Puncuated Equilibrium |
A theory that speciation occurs during brief periods of rapid genetic change |
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Coevolution |
The mutual modification of two different species interacting with each other |
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Sexual Selection |
The preferential choice of a mate based on a specific phenotypic trait |
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Principle of Uniformitarianism |
Principle that says geological structure of the earth resuited from cycles of observetable processes and that the same process operate continually through time |
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Endosymbiosis |
A theory of the evolution of eukaryotes by the formation of a mutualistic relationship between two prokaryotes |
