BIAN2013 HUMAN EVOLUTION Mondays, 12, MCC T2 Thursdays, 910, MCC T3 Evolution

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BIAN2013HUMAN EVOLUTIONMondays, 1-2, MCC
T2Thursdays, 9-10, MCC T3Evolution
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ESSAY WRITING

• Harvard system for references
• Cite author of chapter, not editor of book
• Chinese names
• surname is usually first
• Surname is always single-syllable
• In your own words
• not too many direct quotes
• Avoid
• Sweeping statements
• However
• Greengrocers apostrophe

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(No Transcript)
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What is Evolution?

• Darwins definition
• Descent with modification

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Mechanisms of evolution

• Natural selection
• Differential survival and/or reproduction
• Concept is Fitness
• Mutation
• Random change in a gene
• Drift
• Random fixation of a mutation
• Molecular Drive
• Directed genetic change
• A bit controversial

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Mutations occur all the time

• Usually they disappear from the population
  shortly after they appear
• A very few become fixed, by chance alone

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The larger the population, the more mutations
there are The smaller the population, the more
chance one will be fixed Therefore neutral
evolution depends on time alone
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Is evolution necessarily gradual?
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What phylogeny looks like under the two modes
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An apparent case of punctuated equilibriamollusc
s of Lake Turkana
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The Effect Hypothesishow a series of
punctuations can mimic gradualism