The structural adaptions observed in placental mice, in North America, are very similar in appearance to marsupial mice in Australia. It is an example of

Options

A. Divergent evolution
B. Parallel evolution
C. Homology
D. Analogy

Answer

To solve the question regarding the structural adaptations observed in placental mice in North America and marsupial mice in Australia, we will analyze the provided options step by step.

### Step-by-Step Solution:

1. **Understanding the Question**:
- The question states that placental mice in North America and marsupial mice in Australia have similar structural adaptations. We need to identify the type of evolutionary process this similarity represents.

2. **Analyzing the Options**:
- **Divergent Evolution**: This occurs when two or more species that share a common ancestor evolve different traits. This does not apply here since placental and marsupial mice do not share a recent common ancestor.
- **Homology**: This refers to structures that are similar due to shared ancestry but may serve different functions. The similarity in appearance between the two types of mice does not stem from a common ancestor.
- **Analogy**: This describes structures that have similar functions but evolved independently. However, in this case, we are looking for structural similarities, not functional ones.
- **Parallel Evolution**: This occurs when two species that do not share a recent common ancestor evolve similar traits independently, often due to similar environmental pressures.

3. **Identifying the Correct Answer**:
- Since placental mice and marsupial mice are different species that have evolved similar adaptations independently, the correct answer is **parallel evolution**.

### Final Answer:
The structural adaptations observed in placental mice in North America and marsupial mice in Australia are an example of **parallel evolution**.

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