Question

Explain in brief - Lamarck’s principle of ‘use or disuse of organs’.
b) Give two examples.
c) What are ‘acquired characters’?

Answer 1

Jean Baptise Lamarck put forth the principle of use or disuse of organs. According to him, the morphological changes are responsible for evolution and the activities or laziness of the animals are responsible for those morphological changes.

Examples - 1. The neck of giraffe has become very long due to browsing on leaves of tall trees

2. The shoulders of ironsmith have become strong due to constant hammering movement

3. The wings of birds like emu, ostrich have become weak due to no use at all.

All these are examples of acquired characters which are transferred from one generation to the next generation. This is called Lamarckism.

Answer 2

Answer:

principle of use or disuse of organs