Extinction

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 since 18 June 1999 


These are lecture notes from an experimental non-majors biology class taught in 1995 by Bruce Walsh, University of Arizona. Other lectures of potential interest:

  • Origins of life
  • Cosmic impacts and life on Earth
  • Genetics class lecture notes


  • Extinction
  • Mass extinctions
  • The Cambrian Extinction (500 MYA)
  • The Devonian Extinction (345 MYA)
  • The Permian Extinction (230 MYA)
  • Triassic extinction (80 MYA)
  • Quaternary (Pleistocene epoch) extinction 20,000 YA
  • Causes of extinction: Overexploitation
  • Causes of extinction: Introduction of Pests, Predators and competitors
  • Causes of extinction: Habitat destruction
  • Risks faced by small populations
  • Demographic stochasticity
  • Genetic stochasticity
  • Effective population size, Ne
  • Ne with unequal sex ratios

  • Short-term Genetic risks faced by small populations
  • Long-term Genetic risks
  • Genetic Vs. demographic stochasicity
  • Why save species?