Natural selection is the process by which nature selects biological characteristic which is adaptive to the environment. It is the mechanism of evolution. All organism are different naturally in their way. It is characteristic which helps them to adapt and reproduce.
Charles Darwin developed the idea of natural selection. He made this idea public through his famous book "The origin of species." All species have unique physical characteristics which are the outcome of natural selection. They are adaptive to the environment.
For example, a giraffe has a long neck which is the natural selection. Initially, the giraffe had a shorter neck. The long neck enables giraffe to feed on leaves easily which are at height. This characteristic enhances to fit in the environment to survive and reproduce.
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| Giraffe long neck is due to natural selection. |
Why birds are different from island to island? Darwin concluded, it is because of natural selection. Among different variation on the attribute of bird, he studied about the beak of bird varied from island to island. He linked beak shape with the texture of food grains and the ways they acquired. Bird with larger beak consumed harder food grains, and smaller beak consumed softer food grains. This fact concludes beaks are the outcome of adaptation to food grains available on the environment.
There is variation in biological traits and it is transferred from one generation to another generation. All the variations are to adopt with the environment. In this way, natural selection occurs. This theory helps to know about the origin of different species and their evolution. It helps to know how and why we are in the present biological traits.
For example, at one time in prehistory, humans were quadrupedal (four-legged) but now we are two-legged. It is because we engaged in tool-making for hunting and nature selects us to be bipedal(two-legged.)
If we see any species in this world, it means they can adapt to their environment. The species without the characteristic of adaptation can exist no longer. They will extinct.
Natural selection is in contrast with artificial selection. In this process, the human selects the organism to change and reproduce. Farmer select plant and animals to reproduction with their desire result.
Darwin theory, the idea of natural selection helps to avoid much illusion created by different religious myth. Many religion claims that we are the creator of god. But this theory illustrates clearly that our evolution is based on natural selection.