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Tectonic uplift can alter the drainage patterns of rivers ,thereby isolating populations of many species. Population isolation of this kind results from which one of the following processes?

 What is Vicariance ?

Vicariance:



Vicariance is a process in biogeography where a population of organisms becomes geographically separated by a physical barrier, such as mountains, rivers, or changes in climate. This division halts gene flow between the separated groups, eventually leading to the formation of new species. For instance, when a river emerges and divides a population of animals, each group may undergo independent evolution due to genetic drift, natural selection, and varying environmental conditions. This concept is fundamental in evolutionary biology and illustrates how species diversify across different geographic areas.

Question: (CSIR DECEMBER 2024)

Tectonic uplift can alter the drainage patterns of rivers ,thereby isolating populations of many species. Population isolation of this kind results from which one of the following processes?

  1. Dispersal
  2. Vicariance
  3. Range expansion 
  4. Competitive exclusion
Answer:  2.Vicariance




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