ecology feb 2 - Evolution Natural selection Certain things...

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Evolution Natural selection Certain things happen that allow individuals to survive gene inheritance variant = alleles - depends which gene gets expressed - some genes have 2 possibilities, some 3, some 4 - for natural selection, we know that the allele frequency is changing Micro-evolutionary mechanisms can alter the allele frequencies in 4 ways - 1. Natural Selection o predominantly white before industrial revolution- after, with all the soot, it was black that was dominant - 2. Mutation o sickle cell anemia- good if living in Africa; no malaria change allele advantageous traits neutral- hair color - 3. Gene flow o gain or loss of alleles from a population die to movement of individuals o immigration o migration- add new alleles, lose alleles by bringing in new people - 4. Genetic drift- random changes in allele frequency in a population o criteria small population o Example) if the whole world was wiped out instead of this room A. Bottleneck effect- start off with a large population, all kinds
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This note was uploaded on 02/04/2012 for the course ECOLOGY 101 taught by Professor Dr.clark during the Spring '07 term at Rutgers.

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ecology feb 2 - Evolution Natural selection Certain things...

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