Written by the Fiveable Content Team โข Last updated August 2025
Verified for the 2026 exam
Verified for the 2026 examโขWritten by the Fiveable Content Team โข Last updated August 2025
Definition
Postzygotic barriers are mechanisms that occur after the formation of a zygote (fertilized egg) between individuals of different species. These barriers reduce the fitness or reproductive success of hybrid offspring.