Causes of extinction of stellar's sea cow of Russia and passenger pigeon is

Options

A. over-exploitation by humans
B. alien species invasion
C. habitat loss and fragmentation
D. co-extinction

Answer

**Step-by-Step Solution:**

1. **Understanding Extinction**: Extinction refers to the end of an organism or a group of organisms, typically due to a significant decline in population that cannot be reversed.

2. **Identifying the Species**: The question mentions two specific species: Steller's sea cow and the passenger pigeon. Both are known to be extinct.

3. **Recognizing Human Impact**: It is crucial to acknowledge that human activities have significantly contributed to the extinction of many species. This includes overhunting, habitat destruction, and other forms of exploitation.

4. **The Evil Quartet**: There are four main reasons for species extinction, often referred to as the "evil quartet." These include:
- Overexploitation
- Habitat loss
- Invasive species
- Co-extinction

5. **Analyzing Steller's Sea Cow**: Steller's sea cow was a large marine mammal that was hunted extensively by humans for its meat and hide. Being a docile creature, it was unable to escape from human hunters, leading to its rapid decline and eventual extinction.

6. **Analyzing Passenger Pigeon**: The passenger pigeon was once one of the most abundant bird species in North America. However, it was hunted on a massive scale for its meat, and the population was not able to recover due to the intensity of hunting and habitat destruction.

7. **Conclusion**: Both Steller's sea cow and passenger pigeon went extinct primarily due to overexploitation by humans. This highlights the need for sustainable practices in utilizing natural resources to prevent further extinctions.

**Final Answer**: The causes of extinction of Steller's sea cow and passenger pigeon are primarily due to overexploitation by humans.

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