Non–obligatory mutualism is also known as –

Options

A. Commensalism
B. Proto–cooperation
C. Helotism
D. Exploitation

Answer

**Step-by-Step Solution:**

1. **Understanding Mutualism**: Mutualism is a type of symbiotic relationship where two different species interact in a way that benefits both parties.

2. **Defining Non-obligatory Mutualism**: Non-obligatory mutualism refers to a type of mutualism where the species involved can survive independently without the relationship. This means that while both species benefit from the interaction, they do not rely on each other for survival.

3. **Identifying the Correct Term**: The term that is synonymous with non-obligatory mutualism is "proto-cooperation." In proto-cooperation, both species gain advantages from their interaction, but it is not essential for their survival.

4. **Examples of Non-obligatory Mutualism**:
- An example of proto-cooperation is the relationship between cattle and egrets. Egrets eat parasites off the cattle, benefiting from food while the cattle get rid of pests.
- Another example is the relationship between fungi and algae in lichens, where fungi provide shelter and algae produce food through photosynthesis.

5. **Conclusion**: Based on the definitions and examples discussed, non-obligatory mutualism is also known as proto-cooperation.

**Final Answer**: Non-obligatory mutualism is also known as proto-cooperation.

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