Reproductive Isolation Short Note | Evolution Class 12 Notes

In this article we will discuss about Reproductive Isolation :- Prezygotic isolation and  Postzygotic isolation

  • Prevention of inter breeding between the population of two different or closely related species
  • Reproductive isolation was explained by stebbian
  • Two types reproductive isolation are
    1. Prezygotic isolation
    2. Postzygotic isolation

1. Prezygotic isolation

  • Prevention of mating and the formation of zygote
    • Temporal isolation: Due to difference in breeding seasons of two species
    • Ecological isolation: Due to different habitats of two species
    • Behavioral isolation: Due to different sexual or coitus behavior of two species

2. Postzygotic isolation

  • The organisms mate but no offspring are produced
    • In viability: Zygote fails to develop
    • Sterility: Adults are sterile and do not produce gametes
    • Hybrid Breakdown: Sometimes inter specific mating produces a hybrid, but progeny is weak, abnormal or sterile.

Reproductive Isolation

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