According to the Neo-Darwinian theory,which of the following is responsible for the origin of new species?

If gene migration happens multiple times,it would lead to

Given below are the two statements.
Statement $I$: Directional isolation favours the intermediate forms and eliminates both phenotypic extremes.
Statement $II$: In directional isolation,more individuals acquire a value other than the mean character value.
In the light of the above statements,choose the correct answer from the options given below:

Which one of the following was the contribution of Hugo de Vries?

Discuss natural selection and artificial selection. What are the implications of the latter on the process of evolution?

The diagram given below represents the operation of natural selection on different traits. Choose the correct option.