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While creation and presence of variation...

While creation and presence of variation is directionless, natural selection is directional as it is in the context of adaptation. Comment.

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There are many sources of variations e.g. mutations, recombination of genes during the process of sexual reproduction due to crossing over, chance arrangement of bivalents and chance fusion of gametes, hybridisation, physical and chemical mutagens, genetic drift, etc. These variations are non-directional as can appear in any direction. Due to variations, the populations become heterogeneous and act as raw materials. Natural selection favours the more adapted members than less adapted ones for faster reproduction so contributing greater percentage of their genes to the progeny. This gives a specific direction to the evolutionary trend
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