Select the species which are extincted due to over exploitation. Nile perch, water hyacinth, african catfish, passenger pigeon, lantana, cichild fish, steller's sea cow, quagga, dodo.

Answer

To determine which species have gone extinct due to over-exploitation, we can analyze each option provided in the question:

1. **Nile Perch**: This species is not extinct; it is still present in various water bodies, particularly in Africa. It has been involved in ecological changes but is not a victim of extinction due to over-exploitation.

2. **Water Hyacinth**: This is an invasive aquatic plant and not an animal species. It has not gone extinct; rather, it has proliferated in many areas, causing ecological issues.

3. **African Catfish**: This species is also not extinct. It is widely farmed and remains abundant in various habitats.

4. **Passenger Pigeon**: This bird species is indeed extinct due to over-exploitation. It was hunted extensively in the 19th century, leading to its decline and eventual extinction.

5. **Lantana**: Similar to water hyacinth, lantana is a plant species and not extinct. It is considered invasive in many regions.

6. **Cichlid Fish**: While some species of cichlids may be threatened, the group as a whole is not extinct. Many species are still thriving in their natural habitats.

7. **Steller's Sea Cow**: This marine mammal was hunted to extinction in the 18th century due to over-exploitation for its meat and hide.

8. **Quagga**: This subspecies of the plains zebra was hunted to extinction in the late 19th century due to over-exploitation.

9. **Dodo**: The dodo bird is famously known for its extinction in the 17th century, primarily due to over-exploitation by humans and introduced species.

Based on this analysis, the species that have gone extinct due to over-exploitation are:

- Passenger Pigeon
- Steller's Sea Cow
- Quagga
- Dodo

### Final Answer:
The species that are extinct due to over-exploitation are:
- Passenger Pigeon
- Steller's Sea Cow
- Quagga
- Dodo