कोशी का प्रवेश द्वार — मानसी जं० - Prabhat Sharan

For a new organism to be formed, induced mutation is responsible. Either bcoz of high exposure to UV radiation or any chemical agent. Spontaneous mutation never leads to a formation of new species else we would be seeing every now and then a new sub-species of homo sapiens around us. At the time of origin of life, earth had volatile environment that facilitated mutation which isn't present in current scenario.

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