The age of Planet Earth has been estimated at about 4.5 billion (4,500 crore) years through methods employed by chemists. The multitude of life forms, particularly flora and fauna, hosted by soil, water and air, both as surviving to this day and those that have moved to the pages of the long history of the Planet make a fascinating study to the informed and also the lay kind, amidst two schools of views, one being creationists and the other evolutionists, keeping aside the former marked by irreconcilable differences in their views, languishing without convincing proof, the latter also being questioned in some circles have caused widespread debates on the origins of species and subsequent many landmark events that tell the fascinating story of evolution, particularly of humankind. The name of naturalist and biologist Charles Darwin (1809-1881) stands out in the context of revolutionary ideas at the root of his theory of natural selection setting forth the modern evolutionary synthesis.
All species constituting the life forms that have made Planet Earth their home are known to have emerged, lived and perished in compliance of natural selection theory of Darwin except the human species indulging in meddlesome intervention such as in vitro fertilisation, genetic modification, DNA technology, seeking remedies and cures for diseases using drugs as well as invasive and non-invasive methods. Thus, the phenomenon of evolution of human species began the story behind the present profile of humans.
