Define adaptive radiation.

Explanation

**Step-by-Step Solution:**

1. **Definition of Adaptive Radiation**:
- Adaptive radiation is a process in evolution where different species evolve from a common ancestor and adapt to various environments within a specific geographical area.

2. **Key Characteristics**:
- This process involves the evolution of different species starting from a single ancestral species.
- These species adapt to different habitats and ecological niches, leading to diverse forms and functions.
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