Biogeography

• Biogeography

  • Study of the distribution of extant and extinct species in specific geographical regions. 
  • These studies prove that closely related species usually occur in the same geographical region and this may suggest that they share a common ancestor. 
  • Biogeographical regions may be isolated by barriers, preventing the spread of species from one region to another. This can lead to the formation of new species. 
  • Barriers: mountains, oceans, deserts, etc. 
• Ancestry

  • Plant and animal life in different geographical regions with similar habitats and climates, but separated by a geographical barrier, may differ drastically and therefore might not share a common ancestor. 
  • Flightless birds may have come from a common ancestor. The birds were separated geographically when Gondwanaland broke. Continental drift caused the climate and habitat change. The birds adapted to the new environment. New species develop due different mutations in the environment. 
• Darwin’s Theory of Evolution

  Individuals of the same species that are geographically separated, adapt to their changed conditions, and undergo different mutations and may develop into new species.