Who have recently tried to put price tag on nature's life support services ?

Options

A. Nile Perch and his colleagues
B. Herbert Boyer and his colleagues
C. Ramdeo Mishra and his colleagues
D. Robert Constanza and his colleagues

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks who has recently attempted to assign a monetary value to nature's life support services.

2. **Review the Options**: The options provided are:
- Nile Perch and his colleagues
- Harbat Boer and his colleagues
- Ramdeo Mishra and his colleagues
- Robert Constanza and his colleagues

3. **Analyze Each Option**:
- **Nile Perch and his colleagues**: Nile Perch is a type of freshwater fish, not a person who would conduct research on ecosystem services. Thus, this option is incorrect.
- **Harbat Boer and his colleagues**: Herbert Boer is known for contributions in biotechnology, particularly in genetic modification. His work does not relate to putting a price tag on nature's services, making this option incorrect.
- **Ramdeo Mishra and his colleagues**: Ramdeo Mishra is recognized as the father of Indian ecology and has made significant contributions to understanding tropical ecosystems. However, he is not known for assigning economic values to ecosystem services, so this option is also incorrect.
- **Robert Constanza and his colleagues**: Robert Constanza is known for his work in ecological economics and has indeed attempted to assign monetary values to ecosystem services, making this the correct option.

4. **Conclusion**: The correct answer is Robert Constanza and his colleagues, who have recently tried to put a price tag on nature's life support services.

---