According to Charles Darwin's theory of natural selection, only those individual are able to survive that adapt better to the changing environment and are able to reproduce. Whereas according to Lamarck, the characters that an individual gains during its lifetime are passed on to its further generations.
Natural selection is the phenomenon that states that only those individuals area able to survive in the environment that adapt better to the changing surroundings and are successfully able to reproduce. The theory was out forward by Charles Darwin.
Characters are the traits that may be phenotypically visible or present at the genetic level. These characters define an individual.
