Contribution of scientist :

$(a)$ Charles Darwin

$(b)$ Lamarck

Comment on the statement that ''evolution and natural selection are end result or consequence of some other processes but themselves are not processes''.

Origin of different types of beaks occur due to

Explain theory of inheritance of acquired characters with proper example.
 

The scientists believe that evolution is gradual. But extinction, part of evolutionary story, are 'sudden' and 'abrupt' and also group-specific. Comment whether a natural disaster can be the cause for extinction of species.