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Question
Write a short note based on the information known to you.
Lamarckism
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Solution
- Lamarck gave the principle of use or disuse of organs. He proposed that the reason behind evolution was the changes in the morphological activities of the organism.
- For example, a giraffe has a long neck because it used to browse on leaves of tall plants by extending their neck for several generations; the shoulders of an ironsmith are strong due to repetitive hammering movements; the wings of an ostrich and emu are weak because they are not used for flying; and the legs of birds and swans are used for swimming because they live in water.
- These characters are termed acquired characters and are transferred from one generation to another.
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