Natural Selection and Evolution

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Natural Selection and Evolution
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Evolution

• Darwin
• Late 1800s
• Historical View of Earth and its organisms.
• HMS Beagle
• Galapagos Islands
• Mechanism of Evolution is Natural Selection.

• Important Terms
• Species
• Population
• Community
• Gene Pool
• Allele Frequency
• Genetic Equilibrium
• Hardy Weinberg Equilibrium

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Evolution Requirements for

• EvolutionA change in the allele frequency of a
  population over time.
• Requirements
• 1. Genetic Variabilitymay come from mutations
  and immigration.
• 2. More offspring are produced than can survive
  (due to limited resources, predation, etc)
• 3. Some organisms must be better adapted than
  others.

• 4. There must be differential reproduction rates
  due to the adaptive characteristics of some
  members.
• Fitness
• Fecundity

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Hardy-Weinberg Equilibrium

• Genetic Equilibrium
• Hardy-Weinberg Law
• Defined evolution by describing when it would not
  happen.
• There are 5 requirements that must be met for
  genetic equilibrium to occur.

• Requirements
• 1. No mutations.
• 2. No immigration or emigration.
• 3. There must be a very large population in
  order to avoid genetic drift.
• 4. There must be no natural selection.
• 5. There must be no sexual selection.

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Hardy-Weinberg Equilibrium

• Important Terms
• Gene flow
• Genetic Drift
• The Founder Effect
• Ellis-van Creveld Syndrome
• Natural Selection
• Sickle Cell example
• Sexual Selection
• Non random Mating

• Natural Selection Patterns
• 1. Stabilizingbirth weight.
• 2. Directionalpeppered moths DDT resistance
• 3. Disruptiveswallowtail mimicry example.
  Dimorphism or polymorphism

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More on Evolution

• Inbreeding
• Dangers
• Cheetahs
• Pure bred dogs
• Microevolution
• Macroevolution
• Speciation
• Biological Species Concept

• Reproductive Isolating mechanisms
• Prezygotic
• Post Zygotic

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Types of Speciation

• Phyleticgradualism.
• Allopatricseparation by a physical barrier.
• ParapatricOccurs in adjacent populations due to
  local environment problems. Plants and barbed
  wire example

• Sympatricindividuals continue to live with each
  other. Mostly in plants. Due to polyploidy.
• Hybridization

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Patterns of Evolution

• Divergent EvolutionShare a common ancestor, but
  evolve differently.
• Adaptive Radiation
• Why does it occur?
• Convergent Evolutionbecome more alike due to
  environment. Aquatic mammals and fist.

• Parallel EvolutionRelated species remain
  relatively the same due to their environments.
• CoevolutionPlants and pollinators parasites and
  hosts.

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More on Evolution

• Extinction
• Gradualism
• Punctuated Equilibrium
• Adaptive Radiation
• Why does this pattern occur?

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Proof for Evolution

• Homologous features
• Analogous features
• Vestigial organs
• Fossil Record
• Radioactive Dating
• Comparative Embryology
• Comparative Biochemistry and Molecular Biology
• Artificial Selection

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Origins of the World and Life

• Big Bang Theory
• Characteristics of the Pre-life world
• Oparins hypothesis
• Membrane Invagination Hypothesis
• Endosymbiotic Hypothesis

• Phylogenetics