Which postzygotic barriers prevent formation of hybrids beyond the first generations?
A) increased hybrid vulnerability
B) increased hybrid fertility
C) hybrid breakdown
D) hybrid gamete isolation

Question

Quizplus · Accepted Answer

Postzygotic barriers are mechanisms that prevent the formation of viable and fertile hybrids. Hybrid breakdown occurs when the hybrids of the first generation are viable and fertile, but the subsequent generations produced from interbreeding of the hybrids are weak and sterile, leading to a gradual loss of gene flow between the two parent species. Therefore, only option C (hybrid breakdown) explains the prevention of hybrid formation beyond the first generations. The other options, increased hybrid vulnerability, increased hybrid fertility, and hybrid gamete isolation, may prevent hybridization but do not necessarily prevent formation of hybrids beyond the first generations.

Which Postzygotic Barriers Prevent Formation of Hybrids Beyond the First