Question

what is genetic drift?? and define reproductive isolation?

Answer 1

the genetic drift means that variation in the relative frequency of different genotypes in a small population, owing to the chance disappearance of particular genes as individuals die or do not reproduce.and reproduction isolation mean thatReproductive isolation refers to the situation where different species may live in the same area, but properties of individuals prevent them from interbreeding. The things which stop species or groups of organisms reproducing sexually are 

Answer 2

-genetic drift means random changes in gene frequency especially in small population due to some accidental reason.
-reproductive isolation means when member of the particular species are not able to mate with other member of the same species due to geographical barriers.
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