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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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In sexually reproducing organisms variations are non-directional or directionless because they arise
(a) by crossing over during meiosis and
(b) by random fusion of gametes. Natural selection operates at the level of gene pools of the individuals. Organisms whose gene pools are best adapted to the existing environmental conditions are able to survive successfully and produce more offspring. It means environment provides direction with respect to adaptation and natural selection favours the survival and multiplication of better adapted organisms.
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ICSE-EVOLUTION-COMPETITION CORNER (Assertion and Reason Type Questions (For AIIMS aspirants))
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  8. Assertion: Lederberg's experiment explains the genetic basis of adapta...

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  9. Assertion: Ostrich has vestigial wings and feather but is a cursorial ...

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  13. Assertion: Forelimbs of different vertebrates are basically similar. ...

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  15. Assertion: Many physical and chemical agents induce inheritable mutati...

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  16. Assertion: There is an everlasting competition between individuals hav...

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  17. Assertion: Evolution is adaptation through generations. Reason: Only...

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  18. Assertion: Natural selection is not the exclusive force of speciation....

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  19. Assertion: Human evolution occurred in Asia and Africa. Reason: The ...

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  20. Assertion: Among the primates, chimpanzee is the closest relative of m...

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