Question

explain briefly with the help of examples how new species come up . mention any two factors which are responsible for rise of new species

Answer 1

Factors that could lead to the rise of a new species are:

1)Geographical barrier: Extrinsic geographical barriers such as rivers, mountains, etc between two populations which allows no gene flow and leave them to become new two species.
2) Genetic drift: Accidental change in allele frequencies that may result in extinction of poulation or formation of new species from them.
3) Natural selection: Selection performed by nature, of the best suited varieties ( having favourable variations)to survive and destruction of the less suited varieties through exposure to environmental stresses.