Define speciation. What are the factors which lead to speciation?
The process of formation of new species from the existing species is called speciation. The factors which lead to the formation of new species are: (i) Reproductive Isolation: (a) Allopatric speciation: Caused by the various types of barriers like mountain ranges, rivers, seas, etc. It leads to reproductive isolation between members of the species and this is also called geographical isolation. (b) Sympatric speciation: It occurs when populations of a species that share the same habitat become reproductively isolated from each other. (ii) Genetic Drift: It is caused by change in the frequency of a particular genes by accident or by chance alone. (iii) Natural Selection: The process by which a group of organisms adopts to fit their environment in a better way. (iv) Migration: When movement of a section of population to another place and population occurs. (v) Mutation: Sudden changes in the sequence of DNA.
