The classical example of adaptive radiation during formation of new species is

Options

A. Marsupials of Australia
B. Darwin's finches
C. Giant tortoise
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Adaptive Radiation**:
- Adaptive radiation is a process where organisms rapidly diversify from a common ancestor into a variety of forms. This typically occurs when there is a change in the environment that creates new resources or opportunities.

2. **Identifying Examples**:
- The question asks for classical examples of adaptive radiation. Some well-known examples include:
- **Darwin's Finches**: A group of finches that evolved from a common ancestor into multiple species, each adapted to different ecological niches in the Galápagos Islands.
- **Marsupials of Australia**: These mammals diversified into various forms to occupy different ecological roles in Australia, adapting to different environments.
- **Giant Tortoise**: The giant tortoises of the Galápagos Islands also illustrate adaptive radiation, as they evolved distinct forms based on the specific islands they inhabit.

3. **Evaluating the Options**:
- The question provides multiple choices: marsupials of Australia, Darwin's finches, giant tortoise, or all of the above. Since all these examples illustrate adaptive radiation, the correct answer is "all of the above."

4. **Conclusion**:
- Therefore, the classical example of adaptive radiation during the formation of new species includes all the mentioned options.

**Final Answer**: All of the above.

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