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.
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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.
- 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.