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ORIGIN OF REPRODUTIVE ISOLATION

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  What is reproductive isolation?? It is a prevention of interbredding between the population of two different or closely related species. Can lead to the formation of new species (speciation). Reproductive isolation functions in two mechanism--- 1)Prezyotic  2)Postzygotic PREZYGOTIC MECHANISM   It works before the formation of zygote.i.e before fertilization has occurred.  In this the nature tries to prevent fertilization. It includes:- a)Ecological barrier It is also known as geographical isolation.Here the species lives in two different habitat. Due to their differences in habitat mating is not possible.  Eg.Suppose species '1'lives in freshwater and species '2'lives in terrestrial. So fertilization is not possible between them. b)Temporal isolation  In this isolation,the breeding seasons of species are different.  Due to the differences in breeding season,they don't mate.  Eg.Suppose species '1' has breeding season from April till November and...