Question

Explain the theory of Lamarckism with the help of any two suitable examples.

Answer 1

The theory of Lamarckism, proposed by Jean-Baptiste Lamarck, states that the morphological changes occurring in living organisms are responsible for evolution. These changes are driven by the “use or disuse of organs” and the “inheritance of acquired characters.”

Examples:

1. Giraffe’s Neck: Ancestors of giraffes were short-necked. Due to the need to reach leaves on high branches during droughts, they kept stretching their necks. This “acquired” long neck was passed to the next generation.
2. Blacksmith’s Shoulders: The shoulders of a blacksmith become very strong because of the frequent and vigorous movement of hammering iron.
3. Flightless Birds: Wings of birds like the Ostrich or Emu became weak because they stopped using them for flying.