Question

Observe the picture and answer the following questions.

1. The given picture indicates which principle?
2. Explain that principle in your language.
3. What is the meaning of acquired characteristics?

Answer 1

1. The given picture indicates Lamarckism or inheritance of acquired characters.
2. Lamarckism or inheritance of acquired characters:
   i. Lamarckism is the theory of inheritance of acquired characters from one generation to another, given by Jean-Baptiste Lamarck.
   ii. It states that the morphological changes occurring in living organisms are responsible for evolution. This concept was based on the principle of use and disuse of organs.
   iii. Morphological changes may occur gradually, either due to specific activities or laziness of a particular organism.
   iv. For e.g. Browsing on leaves of tall plants caused the neck of the giraffe to become long; frequent hammering movements cause the shoulders of ironsmith to become strong; inactivity caused weakening of the wings of birds like emu; legs of swans and ducks have become useful for swimming due to living in water; due to burrowing habits, snakes have lost their legs; etc.
3. Modification in structure or function acquired by an organism during its life, caused by environmental factors is known as acquired character.