Question

Jean-Baptiste Lamarck explained evolution based on
A. Natural selection
B. Survival of the fittest
C. Mutations
D. Inheritance of acquired characteristics

Answer 1

Hint: In terms of biology, evolution is the change in the characteristics of a species that results in the formation of new species over a period of time.

Complete Answer:
- Jean-Baptiste Lamarck was a French naturalist. He was a soldier, biologist who proposed the idea of evolution. He was the first who proposed a mechanism by which gradual changes in the species occur.
- His theory of evolution was based on the principle that physical changes occured in the lifetime of any organism can be transmitted to their offspring.
- These physical changes may include developments or any organ, or development of any part, etc.
- The physical changes occur in the somatic cells of a person. As these changes are acquired by the person due to some environmental conditions that’s why these changes are called as acquired characteristics.
- So, his theory was based on the principle of ‘inheritance of acquired characteristics’. The theory of Jean-Baptiste is known as Lamarckism.

Example of Lamarckism theory:
- Long neck of Giraffe was the example given by Lamarck in order to prove his theory.
- Giraffes stretch its neck in order to obtain fruits from the higher trees.
- The continuation of this process results in gradual lengthening of the limbs and neck or giraffe after a long period of time. And this acquired character is passed on to their offsprings.

Hence, option D is the right answer for this question.

Note: Lamarckism, or Lamarckian inheritance, also known as "Neo-Lamarckism", is the notion that an organism can pass on to its offspring physical characteristics that the parent organism acquired through use or disuse during its lifetime.