Patterns of Evolution: Convergent Evolution, Coevolution

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Patterns of EvolutionConvergent
Evolution,Coevolution Divergent Evolution
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Convergent Evolution

• Occurs when different organisms that live in
  similar environments become more alike in
  appearance and behaviour.
• The environment selects similar adaptations in
  unrelated species.
• Organisms develop analogous structures (same
  function, but different origins).
• Examples - Bird wings/insect wings
• - Shark fins/dolphin fins

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More examples
Placental Mammals top row Marsupial Mammals
bottom row
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Coevolution

• When two species evolve together.
• There is a mutual evolutionary influence between
  two species.
• The species have a symbiotic relationship
  (interaction between members of two populations).
• Example - Birds and flowers

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Divergent Evolution

• The process by which an ancestral species gives
  rise to a number of new species that are adapted
  to different environmental conditions and are
  less alike.
• Often occurs when a species colonizes a new
  environment.
• Also known as adaptive radiation.
• Examples - Darwins Finches.
• - Brown bears and polar bears

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Divergent Evolution
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