Practice question · Multiple choice
Natural selection systematically favours prezygotic over postzygotic reproductive barriers during divergence. What drives this evolutionary asymmetry, and what does it mean for hybridising taxa?
Hints
- Where along the reproductive timeline is parental investment lost if an incompatible mating proceeds?
- Does natural selection act on the sterile hybrid itself or on the parents that wasted their reproductive effort?
Show the answer
C. Prezygotic isolation avoids the energetic waste of producing non-viable offspring
Why
Postzygotic barriers still consume parental investment before reproductive failure occurs, so selection actively rewards traits preventing wasted gametes. Hybrids are subject to selection through parent fitness, and behavioural divergence is not inherently faster than genetic incompatibility.
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