Related species which are reproductively isolated but morphologically similar are called

Options

A. Allopatric
B. sympatric
C. Sibling
D. Morphospecies

Answer

To answer the question "Related species which are reproductively isolated but morphologically similar are called," we can follow these steps:

### Step 1: Understand the Key Terms
- **Reproductively Isolated**: This means that the species cannot interbreed and produce fertile offspring.
- **Morphologically Similar**: This indicates that the species look very similar in terms of physical characteristics.

### Step 2: Identify the Types of Species
- **Allopatric Species**: These species are separated by geographical barriers, leading to speciation. However, they are not necessarily morphologically similar.
- **Sympatric Species**: These species exist in the same geographical area but are reproductively isolated. They may have evolved from a common ancestor but are not specifically defined by morphological similarity.
- **Sibling Species**: These are species that are very similar in appearance (morphologically similar) but are reproductively isolated from each other.

### Step 3: Analyze the Options
- The question asks for species that are both morphologically similar and reproductively isolated.
- Among the options discussed, "sibling species" fits this description perfectly.

### Step 4: Conclusion
The correct answer to the question is **sibling species**.

### Final Answer
Related species which are reproductively isolated but morphologically similar are called **sibling species**.

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