Final answer:
Hybrid reproduction may cause two species to fuse into one if the hybrids exhibit higher fitness than the parent species, as this can lead to a breakdown of reproductive barriers and a merger of the species.
Step-by-step explanation:
In what situation would hybrid reproduction cause two species to fuse into one? The correct answer is c) Hybrids having higher fitness than parent species. When hybrid individuals have higher fitness than the parent species, they may have better survival and reproductive success. This can lead to the continuation of reproduction between the hybrids and both parent species, potentially leading to a situation where the previously distinct species become one.
A hybrid is typically produced when members of closely related species reproduce. If the produced hybrids are more fit, this can diminish the reproductive barriers between the two species and cause them to fuse into a single species. However, if hybrids are less fit, then the opposite occurs, a process called reinforcement, which strengthens the divergence between the species.In a situation where the hybrids have higher fitness than parent species, two species can fuse into one. If the hybrids are more fit than the parents, reproduction would likely continue between both species and the hybrids, eventually bringing all organisms under the umbrella of one species.