Which of the following conditions is necessary for adaptive radiation to occur?

• A. A stable environment with little ecological change.
• B. A decrease in the number of available ecological niches.
• C. Limited genetic variation within the ancestral species.
• D. A single ancestral species must diversify into multiple new species.

Answer: (D)

Verified step by step guidance

1. Understand the concept of adaptive radiation: Adaptive radiation is an evolutionary process where a single ancestral species rapidly diversifies into a variety of new forms, particularly when a change in the environment makes new resources available, creates new challenges, or opens new environmental niches.
2. Identify the necessary conditions for adaptive radiation: For adaptive radiation to occur, there must be ecological opportunities, such as unoccupied niches, that allow the species to diversify and adapt to different environments or resources.
3. Recognize the role of genetic variation: Genetic variation within the ancestral species is crucial as it provides the raw material for natural selection to act upon, leading to the development of new species adapted to different niches.
4. Consider the impact of environmental changes: Adaptive radiation is often triggered by significant environmental changes that create new ecological niches or reduce competition, allowing the ancestral species to exploit these new opportunities.
5. Conclude with the correct condition: The necessary condition for adaptive radiation is that a single ancestral species must diversify into multiple new species, each adapted to a specific niche or environment, driven by ecological opportunities and genetic variation.