10th Class Science Heredity and Evolution Darwins Theory of Evolution

         Darwin’s Theory of Evolution

 Darwin's gave the theory of evolution of species. According to his theory of evolution:

• Within a population there is natural variation of which some are positive and some are negative.
• The population remain constant even though all species produce large number of off springs.
• There is a continuous struggle for food, shelter and matting between the members of the same species.
• Only the individuals with favorable variations will survive and other will eliminate.
• The favorable variations are passed onto next generation.
• The variations accumulated over the long period leads to the evolution of new species.

Another theory of evolution is the theory of natural selection. According to this theory only those traits are passed from one generation to the next which are favorable for the survival and reproduction of the organism. The other traits are not passed on to the next generation.