Q14 of 21 Page 9

State and describe any three factor responsible for the rise of new species. ( CBSE 2014, 2012)

Speciation is the process of development of the new species from the existing one.

The various factors which can lead to speciation are as follows:


1. Genetic drift: Genetic drift is caused by the change in the frequencies of a particular gene and is also responsible for the growth of a particular trait within the population.


2. Through Geographical isolation method which can be done by the use of various barriers such as mountains, rivers etc. It helps in reproductive isolation and thus promoting the growth of a particular trait in an individual.


3. Adoption of variation due to natural selection method.


4. Isolation of sub-population by ecological barriers.

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