natural selection notes

natural selection notes - Evolution- is a change in the...

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Evolution - is a change in the normal form of a species over many generations as a result of interactions with the biotic and abiotic environment. Natural Selection - is the differential survival and/or fecundity (ultimately leading to differential fitness) of individuals with different form/traits as a result of interactions with the biotic and abiotic environment. Directional selection - individuals with the rare form or trait leave more descendents than individuals with the normal form of the trait. Usually due to a change in the environment that causes a shift in the normal form, where the rare form becomes the favored form. Example: the selection for dark wing/body in the peppered moths. Example: finch population evolved to have slightly larger bill size due to increased seed hardness. Stabilizing selection - individuals with the rare trait leave fewer descendents then individuals with the normal form of the trait. This is most common in environments that have remained unchanged for many years. Example: selection against white flowers in the larkspur, or the purple larkspur was
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This note was uploaded on 02/12/2010 for the course BIOL 202-004 taught by Professor Dr.johnson during the Fall '09 term at Butler CCC.

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natural selection notes - Evolution- is a change in the...

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