Which of the following is not a key aspect of an adaptive radiation?

• A. Rapid diversification of species
• B. Adaptation to different ecological niches
• C. Common ancestry of species
• D. Gradual evolution over millions of years

Answer: (D)

Verified step by step guidance

1. Understand the concept of adaptive radiation: Adaptive radiation is a process in which organisms diversify rapidly into a multitude of new forms, particularly when changes in the environment make new resources available, create new challenges, or open new environmental niches.
2. Identify the key aspects of adaptive radiation: These typically include rapid diversification of species, adaptation to different ecological niches, and common ancestry of species.
3. Analyze the options provided: Rapid diversification of species, adaptation to different ecological niches, and common ancestry of species are all characteristics of adaptive radiation.
4. Consider the option 'Gradual evolution over millions of years': Adaptive radiation is characterized by rapid changes rather than gradual evolution, which is more typical of other evolutionary processes.
5. Conclude that 'Gradual evolution over millions of years' is not a key aspect of adaptive radiation, as it contradicts the rapid nature of the process.