Question

Lamark’s theory of evolution is also known as
A) Natural selection
B) Inheritance of acquired characters
C) Survival of the fittest
D) Mutation theory

Answer 1

Lamarckism or Lamarckian inheritance is the belief that an organism may transfer to its descendants the traits that it has gained over its lifespan. It is also known as the inheritance of inherited characteristics or soft inheritance.

Complete Answer:
Lamarckism was proposed by Jean-Baptiste de Monet Lamarck in the years 1744-1829. This hypothesis was founded on the idea that all physical changes arising in a person over his or her lifetime are inherited by his or her offspring.
Lamarck’s theory includes four main propositions namely,

Change through use And disuse:- The organs that are commonly used by the organism grow and the features that are seldom used are lost in the next generation. The organs that the species have avoided using will shrink with time.
Organisms are driven to larger Complexity:- When species adapted to their environment, they grew more and more complex from simpler forms. Lamarck believed in life's inevitable generation.
Inheritance of acquired features:- During a lifespan, a person acquires those characteristics. These characters are also inherited from their children.
Effect of Environment and New Needs:- The climate impacts all species. A small change in the climate induces changes in animals. This gives rise to new needs which, in turn, establish new systems and change the behaviours of species.
Hence, Lamarck's philosophy of evolution is often referred to as the inheritance of acquired characters.

The correct answer is option ‘B’, Inheritance of acquired characters.

Note: One example for Lamarckism is Evolution of giraffes. The ancestor of the giraffe appeared like horses with short heads and forelimbs. They existed in areas where there was little grass on the earth. They had to extend their arms and forelimbs to eat leaves from tall plants. As a result, these sections have become elongated. This characteristic has been replicated in centuries to come.