. What is meant by speciation? List four factors that could lead to speciation
Which of these cannot be a major factor in the speciation of a self-pollinating plant species. Give reason to justify your answer.
Ans. Speciation. The process by which new species develop from the existing species by evolution or any genetic modification of previous species is known as speciation.
The important factors which could lead to the formation of new species are:
(i) Geographical isolation of a population caused by various types of barriers like mountain ranges, rivers, sea etc. The geographical isolation leads to reproductive isolation due to which there is no flow of genes between separated groups of population.
(ii) Genetic drift caused by drastic changes in the frequencies of particular genes by chance alone.
(iii) Variations caused in individuals due to natural selection.
(iv) Drastic change in the genes or DNA called mutation is also a cause of speciation. Reproductive isolation cannot be a major factor for the speciation of a self-pollinating plant species as it does not depend on any other plant for its reproduction process.