Association between barnacle and Limulus is :

Options

A. Symbiosis
B. Commensalism
C. Parasitism
D. Predatorship

Answer

To determine the type of association between barnacles and Limulus, we can follow these steps:

### Step 1: Understand the Types of Associations
First, we need to understand the different types of ecological associations:
- **Symbiosis**: Both organisms benefit from the relationship (plus-plus).
- **Commensalism**: One organism benefits while the other is neither helped nor harmed (plus-zero).
- **Parasitism**: One organism benefits at the expense of the other (plus-minus).
- **Predatorship**: One organism benefits by preying on another (plus-minus).

### Step 2: Identify the Organisms
In this case, we are looking at barnacles (genus: Balanus) and Limulus (horseshoe crab).

### Step 3: Analyze the Relationship
Barnacles attach themselves to the shell of Limulus. As they move with Limulus through the water, they feed on microorganisms.

### Step 4: Determine the Benefit or Harm
In this relationship:
- Barnacles benefit by getting a place to live and access to food (microorganisms).
- Limulus is not harmed or benefited by the presence of barnacles.

### Step 5: Classify the Association
Since barnacles benefit while Limulus is neither harmed nor helped, this relationship fits the definition of **commensalism**.

### Final Answer
The association between barnacle and Limulus is **commensalism**.

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