Lecture 10 genetic drift, gene flow, and species

Lecture 10 genetic drift, gene flow, and species -...

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“Greetings! I'm looking for survey data on the reasons why people reject evolution. My hunch is that most people who reject evolution do so because they don't want to be connected to the animal world - they don't want to be "from monkeys" or the primodial slime. I'd like to see whether any data exist that could be brought to bear on this hypothesis.” Thanks. Norman Norman Johnson Plant, Soil, and Insect Sciences University of Massachusetts
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Clicker question discussion
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Evolution in the News
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Rapid random changes in gene pool frequencies occurring in a small population are likely due to: a) genetic drift b) founder effect c) bottleneck effect
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Evolution can occur by random forces- Not just natural selection
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Genetic Drift The random fluctuations (or drift) of gene frequencies from generation to generation in a population of small size.
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Genetic Drift
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The founder effect is a small population effect in which the genes of a few people (the population founders) are inherited over time by a large number of descendents.
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Founder Effect
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Founder Effect
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This is the dramatic reduction in genetic diversity of a population or species resulting from an ecological crisis that wipes out most members. The limited genetic diversity of the few survivors is the pool from which all future generations are based. Bottleneck Effect
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The classic Hardy-Weinberg Law states that the relative frequencies of genoytpes and phenotypes in large, randomly mating populations tend to remain constant from generation to generation.
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The law is based on a set of ideal conditions. In order for this law to hold true, you must exclude selection against unfavorable genes, mutations (creation of new genes), and interbreeding with genetically different populations (including immigration and emigration).
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Another factor that can significantly change the genotype ratios in relatively small populations is genetic drift. If it weren't for these exceptions to the Hardy-Weinberg model, there would be no genetic change and evolution would not occur.
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is false? A.It has its greatest effect on gene pool frequencies in small populations. A.It does not operate independently of mutation and
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Lecture 10 genetic drift, gene flow, and species -...

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