Question

Which of the followings is responsible for the divergence of two species from a common ancestor?

a) Reproductive isolation

b) Natural selection

c) Gene flow

d) The founder effect

e) B and D

My processor says is E can you explain me why. I think is A

Answer 1

The correct option is a) Reproductive isolation.

The cause of formation is two different species from one common ancestor is allopatric speciation which involves geographical barrier. Other barrier is sympatric speciation, which include reproductive isolation. Reproductive Isolation is genetically-based differences between populations which prevent genetic exchange between them. If two ecological niches are occupied by a single species, which diverges selection between the two niches can cause reproductive isolation.

Natural selection helps in the selection of characteristics that helps the species to survive and adaptation. Founder effect results in loss of variation and in extreme cases results in speciation.