Define 'evolution'. Why are traits acquired during the lifetime of an individual not inherited?

Evolution:

Evolution is defined as the process of gradual changes in organisms to form more complex forms over a long period.

Acquired traits:

1. The traits that are acquired by an individual through their life experiences by the direct and indirect influence of the environment are known as acquired traits.
2. The characteristics which involve germ cells are only inherited from one generation to the next generation.
3. But acquired traits involve somatic cells of the organism and hence are not passed to the next generation.