The phenomenon of fusion is likely to occur when, after a period of geographic isolation, two populations meet again and ________.
A) an increasing number of infertile hybrids is produced over the course of the next 100 generations
B) no reproduction occurs in the hybrid zone
C) an increasing number of viable, fertile hybrids is produced over the course of the next 100 generations
D) a decreasing number of viable, fertile hybrids is produced over the course of the next 100 generations

Question

Quizplus · Accepted Answer

Fusion occurs when two previously isolated populations come back into contact and interbreed, leading to an increase in the number of viable, fertile hybrids over time. This can eventually result in the two populations merging back into a single gene pool, effectively reversing the speciation process that had initially separated them. Choice A is incorrect because an increasing number of infertile hybrids would not lead to fusion. Choice B is incorrect because no reproduction in the hybrid zone would result in no gene flow at all between the two populations, which would not lead to fusion. Choice D is incorrect because a decreasing number of viable, fertile hybrids would indicate that gene flow between the two populations is decreasing or stopping altogether, which would not lead to fusion.

The Phenomenon of Fusion Is Likely to Occur When, After