Lecture 4 - Gene Flow, Genetic Drift, & Molecular Evolution Flashcards
1
Q
Allelic frequencies
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2
Q
Migration
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3
Q
Genetic drift
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4
Q
Founder effect
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5
Q
Neutral evolution
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6
Q
Phylogeny
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7
Q
Genetic population
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8
Q
Gene flow
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9
Q
Stochasticity
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10
Q
Bottleneck
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11
Q
Molecular clock
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12
Q
Review
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- Variation between individuals within a population is the raw material for evolution by natural selection.
- Looked at the first of four mechanisms of microevolutionary change (defined as a change in allele frequency within populations) (LIST THEM)
- When we look at the world, we naturally group organisms into categories.
- We now know that those categories are real & we call them species.
- But even within a species, we see small differences in groupings that we call populations.
13
Q
Goals of lecture
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- We will look at the role of the second and third mechanism of microevolution:
Gene flow & Genetic drift
with the emphasis on change within populations. - In this lecture, we will focus on change within populations.
- But since we believe that these differences between populations can lead to the evolution of new species, biologists are also very interested in understanding the nature of genetic differences between populations and how that variation can ultimately lead to the evolution of whole new species.
- The four mechanisms of microevolution have predictable effects on genetic diversity within populations. Gene flow tends to increase diversity as does mutation. But genetic drift and other stochastic mechanisms tend to reduce diversity.
