Question
What are the different post-zygotic isolating mechanisms?
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Answer
- In post-zygotic or post-mating isolating mechanisms, the two individuals can mate but the result of mating is not favourable.
- Thus the populations remain isolated without the actual genetic exchange.
Post-mating isolating mechanisms are divided into the following categories:
- Gamete mortality : In gamete mortality, there is death of gametes. Sperm transfer may take place but the egg is not fertilized due to gamete mortality.
- Zygote mortality : In zygote mortality, the zygote is formed but it fails to thrive. Though the egg is fertilized the zygote does not survive.
- Hybrid sterility : In this isolation, there is the formation of hybrid as the gametes or zygotes do not die but the hybrid formed is sterile. Sterile hybrid cannot contribute genetically to further generations.
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