Answer the following:

What were the limitations found in Darwinism and Lamarckism?

Darwin had given the concept of natural selection and variations and this theory is known as Darwinism. According to Darwinism environment is continuously changing and in order to survive each organism needs to adapt to the changing environment. But to adapt the environment-organism require certain changes in its previous form and Darwin termed this changes as a variation.

Darwin was very true in his concept that with the changing environment only those who will change and adapt the environment will fit best and survive in nature and these will happen due to certain genetic changes are known as variations.

But there was a certain limitation to this concept which is as follows:

● Darwin had given the concept of variations but he did not have any idea that how these variations arise in a population.

● He does not have any idea regarding the source of variations.

● He also not has any idea that how these variations are inherited or what is the mechanism of inheritance of variations.

Lamarck had given the theory of acquired characteristics which was based on the use and disuse of organism and this theory is known as Lamarckism. According to Lamarck environment is continuously changing and in order to get adapt to the changing environment, each organism has some new needs because if the organism won’t change with the environment there will be no survival. So, according to him in order to fulfill the new needs, the organism makes certain changes in the use of the organs. It happens that in order to fulfill the need they start using one organ at a very higher rate and avoids the use of some organ due to which organ that we continuously use becomes stronger and the one which is rarely used becomes weaker and get extinct. From here the concept of use and disuse of organs was aroused.

But there were certain limitations associated with the Lamarckism which are as follows:

● Lamarck had told that acquired characteristics are inherited by the coming generations. But he was unable to tell that how acquired characters get associated with the reproductive cells.

● Lamarck was unable to explain how acquired characters can be inherited by the future generations.

● Acquired characters can’t be inherited and Lamarck was wrong in his concept of inheritance of acquired characteristics.