In ecology, an association between two animal species in which both partners gain benefit is known as which type of relationship?

Introduction / Context:
In ecology, interactions between organisms are classified into different types based on how each participant is affected. Some relationships harm one partner, some benefit only one, and some provide benefits to both partners. Understanding these basic interaction types is important for topics like ecosystems, food webs and biodiversity. This question asks for the technical term used when both associated organisms gain benefit from the relationship.

Given Data / Assumptions:

- Two animal partners are involved in the association.
- Both partners are benefitted by the relationship.
- Options given are Ammensalism, Commensalism, Colony and Mutualism.
- We assume standard ecological definitions as used in school and competitive exam syllabi.

Concept / Approach:
Mutualism is defined as an interaction between two species in which both species gain a net benefit in terms of survival, growth or reproduction. Classic examples include pollination relationships between insects and flowering plants or cleaning associations between certain fish and larger fish. Commensalism benefits one partner while the other is neither helped nor harmed. Ammensalism harms one partner while the other remains unaffected. A colony is simply a group of organisms of the same species living together and is not a term that directly describes benefit patterns between species.

Step-by-Step Solution:
Step 1: Identify the key phrase in the question, which is that both partners are benefitted.Step 2: Recall that mutualism is defined as a plus plus interaction where both species experience positive effects.Step 3: Commensalism is a plus zero interaction, where only one species benefits and the other is neutral.Step 4: Ammensalism is a minus zero interaction, where one species is harmed and the other is unaffected.Step 5: A colony is not a specific type of interspecific interaction, so the term that matches the described association is mutualism.

Verification / Alternative check:
To verify, think of examples. In mutualism, both species need each other, such as the relationship between certain fungi and algae in lichens, or between rhizobium bacteria and leguminous plants. Each partner provides something valuable to the other. Contrast this with commensalism, such as barnacles on whales, where the barnacle may benefit from transport and food access, while the whale gains no clear advantage. Such comparisons make it easy to confirm that mutualism is the only option where both partners definitely benefit.

Why Other Options Are Wrong:
Ammensalism: In this interaction, one species is harmed while the other is unaffected, so both are not benefitted.
Commensalism: Here one partner benefits but the other partner experiences neither benefit nor harm, so it does not fit a both benefit scenario.
Colony: This term refers to an aggregation of individuals of the same species, such as a colony of ants or bacteria. It does not specify the benefit pattern between two different species.

Common Pitfalls:
Students often confuse mutualism and commensalism because both sound like cooperative interactions. Remember that mutualism means mutual benefit for both, while commensalism is benefit for only one. Also, the term colony is sometimes incorrectly used to describe any group relationship, even though it has a more specific meaning. Carefully linking each term with clear examples and the sign notation plus or minus helps avoid these mistakes.

Final Answer:
The association in which both partners are benefitted is known as Mutualism.