Final answer:
Reproductive isolation leads to the emergence of separate species as it prevents gene flow between populations, allowing them to evolve independently over time. This process, known as speciation, can occur through mechanisms such as geographical barriers that physically separate populations.
Step-by-step explanation:
Reproductive isolation leads to the emergence of separate species through a process known as speciation. When populations of a species become reproductively isolated from each other, they can no longer exchange genes. Over time, mechanisms such as natural selection, mutation, and genetic drift will cause these isolated populations to diverge genetically and phenotypically. A classic example is habitat isolation, where a barrier such as a flood separates populations and restricts gene flow, leading to the independent evolution of the populations.
Allopatric speciation is one outcome of reproductive isolation, where geographical barriers prevent groups within a species from interbreeding. For instance, if a new river forms and divides a population of animals, the separation between populations will prevent gene flow, ultimately resulting in the development of new species. Similarly, if a species of rodent is split by a lake, the lack of gene flow increases the chance of speciation occurring.
Reproductive isolation does not lead to high rates of gene flow, induce mutations, or grant immunity to genetic drift. In fact, in the absence of gene flow, genetic drift can cause certain alleles to become more prevalent within each isolated population.