Final answer:
Reinforcement in a hybrid zone is more likely when the hybrid offspring are less fit than their parent species, leading to increased reproductive barriers and further divergence of the species.
Step-by-step explanation:
The concept of hybrid zones pertains to the area where two closely related species interact and reproduce, creating hybrid offspring. In the context of these zones, reinforcement is more likely to occur when the hybrids are less fit than their parent species. This scenario leads to an increase in reproductive barriers, enhancing the divergence of the parent species until they no longer mate and produce viable offspring, reinforcing the distinction between the two species.
When asking what situation means reinforcement is more likely to occur in the hybrid zone, it refers to the likelihood of reinforcement happening when hybrids are less fit than their parents. In this case, the species would further diverge due to selective pressures that favor the reproduction of the parent species over the less fit hybrids.