Which of the following best describes reproductive isolating mechanisms in the context of speciation?

• A. Adaptations that enhance survival and reproduction within a population.
• B. Factors that promote hybridization between different species.
• C. Processes that prevent gene flow between populations, leading to speciation.
• D. Mechanisms that increase genetic diversity within a single population.

Answer: (C)

Verified step by step guidance

1. Understand the concept of reproductive isolating mechanisms: These are processes that prevent gene flow between populations, which can lead to the formation of new species, a process known as speciation.
2. Identify the types of reproductive isolating mechanisms: They can be prezygotic (before fertilization) or postzygotic (after fertilization). Prezygotic mechanisms include temporal isolation, habitat isolation, behavioral isolation, mechanical isolation, and gametic isolation. Postzygotic mechanisms include hybrid inviability, hybrid sterility, and hybrid breakdown.
3. Consider how these mechanisms contribute to speciation: By preventing gene flow, reproductive isolating mechanisms maintain genetic differences between populations, which can eventually lead to the emergence of distinct species.
4. Evaluate the options given in the problem: The correct description of reproductive isolating mechanisms in the context of speciation is 'Processes that prevent gene flow between populations, leading to speciation.'
5. Reflect on why the other options are incorrect: Adaptations that enhance survival and reproduction within a population do not necessarily lead to speciation. Factors that promote hybridization would increase gene flow, not prevent it. Mechanisms that increase genetic diversity within a single population do not directly lead to speciation.