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Evolution — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYEvolution3 Marks
Question
  1. Explain adaptive radiation with the help of a suitable example.
  2. Cite an example where more than one adaptive radiation have occurred in an isolated geographical area. Name the type of evolution your example depicts and state why it is so named.
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Answer

  1. Darwin finches/black birds (on Galapagos islands), evolved from original seed eating features, into insectivorous & vegetarian features in different habitat/islands.
  2. Australian marsupials and placental mammals. Convergent evolution, more than one adaptive radiation occured in isolated geographical area.

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