Extinction of Stellar's sea cow is due to which of the following reasons :-

Options

A. Habitat loss
B. Over exploitation
C. Alien species invasion
D. Co-extinction

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the reason behind the extinction of Steller's sea cow.

2. **Identifying Possible Reasons**: The extinction of species can occur due to various factors, including:
- Over-exploitation
- Alien species invasion
- Habitat loss
- Co-extinction

3. **Analyzing Over-exploitation**: Over-exploitation refers to the excessive use of natural resources by humans. This can lead to the decline and extinction of species. Steller's sea cow was heavily hunted for its meat and fat, which is a clear example of over-exploitation.

4. **Considering Other Factors**:
- **Alien Species Invasion**: This involves the introduction of non-native species that can disrupt local ecosystems. While this is a significant factor for many extinctions, it is not the primary reason for the extinction of Steller's sea cow.
- **Habitat Loss**: This refers to the destruction or fragmentation of natural habitats. Although habitat loss is a major cause of extinction for many species, Steller's sea cow's extinction was more directly linked to human hunting.
- **Co-extinction**: This occurs when one species' extinction leads to the extinction of another species that is dependent on it. This is not applicable in the case of Steller's sea cow.

5. **Conclusion**: After analyzing the reasons, it is clear that the extinction of Steller's sea cow was primarily due to over-exploitation by humans.

**Final Answer**: The extinction of Steller's sea cow is due to over-exploitation (Option 2).

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