1. Charles Darwin, Spencer is the main supporters of theory.
2. Theory of evolution as 'fittest for the survival' was given by Charles Darwin.
3. Surplus energy theory is given by Herbert Spencer.
4. The surplus energy theory explained that the child's playing (jumping, climbing, running, etc.) was a manifestation of his inner energy.
5. Organisms generally use their energy for survival but children are provided for, resulting in an energy surplus which is rechanneled into play.
6. Another evolutionary theory suggests that play is a method of exercising survival skills that are needed by the individual later in life.