What are the various evidences in favour of evolution?

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heredityandevolution
cbse-class10-science

#1

What are the various evidences in favour of evolution?
OR
Explain with an example for each, how the following provides evidences in favour of evolution in organisms:

  • Homologous organs
  • Analogous organs
  • Fossils

Answer:

The following are the various evidences in favour of evolution:

  • Homologous organs: Organs with a common basic structural design but with different functions are said to be homologous organ. For example, forelimbs of a frog, lizard, bird and man.
  • The forelimbs of man are used for grasping, of lizard for running, of frog for propping up and bird for flying. They have different functions but have same structural pattern.
    image
  • Analogous organs: The analogous organs have different basic structure but perform similar functions. For example, the wing of insects and the wing of birds, have a totally different anatomy and origin but they perform the same function of flying in air.
    image
  • Evidences from fossils: The fossils also provide evidences for evolution. For example, the fossil Archaeopteryx looks like a bird but it bears a number of other features, which are found in reptiles. This observation provides a clue that birds have evolved from reptiles.