The interaction between two living organisms of different species which is beneficial to both but is not obligatory because they can live without each other is known as

Options

A. Proto-cooperation
B. Mutualism or symbiosis
C. Commensalim
D. Amensalism

Answer

To solve the question regarding the interaction between two living organisms of different species that is beneficial to both but not obligatory, we can follow these steps:

### Step 1: Understand the Types of Interactions
First, we need to understand the different types of ecological interactions between species. The question mentions several terms: mutualism, commensalism, amensalism, and proto cooperation. Each of these terms describes a different type of relationship.

### Step 2: Define Each Term
- **Mutualism**: This is a type of interaction where both species benefit from the relationship, and it is often obligatory, meaning they rely on each other for survival.
- **Commensalism**: In this interaction, one species benefits while the other is neither helped nor harmed.
- **Amensalism**: This is a relationship where one species is harmed while the other is unaffected.
- **Proto cooperation**: This is a type of interaction where both species benefit from each other, but it is not obligatory for their survival. They can live independently without the interaction.

### Step 3: Identify the Correct Term
The question specifies that the interaction is beneficial to both species but is not obligatory. Based on the definitions:
- **Mutualism** is not the correct answer because it is often obligatory.
- **Commensalism** does not fit because only one species benefits.
- **Amensalism** is also not applicable as it involves harm to one species.
- **Proto cooperation** fits perfectly as it describes a beneficial interaction that is not essential for survival.

### Step 4: Conclusion
Thus, the interaction described in the question is known as **Proto cooperation**.

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