Ans. 1. Darwin’s theory of evolution is based on natural selection.
2. On the basis of observations, Darwin suggested that only the fittest survive. All those plants and animals which are not fit, die.
3. These fit species reproduce and pass on the relevant characteristics to the following generation which in turn would make them fit for survival.
4. The process of selection of characteristics that contribute to the fitness for survival was called natural selection by Darwin.
5. Only those factors which help any individual to survive are retained and others are lost.
6. This process continues from generation after generations. The total effect is that after several generations, the number of individuals having the relevant factors, that are better adapted to their surroundings, is much more than in the previous generations. These adapted individuals may also be very different from the original species.
7. This process is described as a natural selection of these individuals which have characteristics best adapted for survival.
8. Selection by nature is not deliberate but is natural. The criterion for the natural selection is only one i.e. successful adaptation for growth and reproduction in the given environment.
9. The theory of natural selection which was proposed by Charles Darwin helped to explain the process of development of living things.
10. However, the theory did not explain how an individual plant or animal acquired factors that made it better adapted to its surroundings.
11. In the course of time these questions were answered by the discovery of the laws governing heredity and mutation and thus Darwin’s theory came to be universally accepted.
2. On the basis of observations, Darwin suggested that only the fittest survive. All those plants and animals which are not fit, die.
3. These fit species reproduce and pass on the relevant characteristics to the following generation which in turn would make them fit for survival.
4. The process of selection of characteristics that contribute to the fitness for survival was called natural selection by Darwin.
5. Only those factors which help any individual to survive are retained and others are lost.
6. This process continues from generation after generations. The total effect is that after several generations, the number of individuals having the relevant factors, that are better adapted to their surroundings, is much more than in the previous generations. These adapted individuals may also be very different from the original species.
7. This process is described as a natural selection of these individuals which have characteristics best adapted for survival.
8. Selection by nature is not deliberate but is natural. The criterion for the natural selection is only one i.e. successful adaptation for growth and reproduction in the given environment.
9. The theory of natural selection which was proposed by Charles Darwin helped to explain the process of development of living things.
10. However, the theory did not explain how an individual plant or animal acquired factors that made it better adapted to its surroundings.
11. In the course of time these questions were answered by the discovery of the laws governing heredity and mutation and thus Darwin’s theory came to be universally accepted.
