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• Jean Baptiste de Lamarck


  A French naturalist who was the first evolutionist
• Evolve


  To change gradually
• Lamarck's theories


  • Theory of Need
  • Theory of Use and Disuse
  • Theory of Acquired Characteristics
• Theory of Need


  • Organisms change in response to changes in their environment
  • They develop characteristics necessary to adapt in their modified environment
  • This leads to size increase of body parts or function changes
• Theory of Use and Disuse

  • Organs that are not used will disappear
  • Organs that are constantly used will be developed
• Theory of Acquired Characteristics (Traits)

  Acquired characteristics can be passed on to offspring
• Charles Darwin


  Proposed the Theory of Evolution based on natural selection
• On the Origins of Species by Means of Natural Selection was published


  1859
• Natural selection


  • Favored the survival of long-necked giraffes because it allows them to reach for food on tall trees
  • Short-necked giraffes were eliminated because of their inability to reach higher vegetation when there is scarcity of low vegetation such as grasses
• Genetics Basis of Evolution