Tachyglossus is a connecting link between

Options

A. Reptiles and mammals
B. Reptiles and birds
C. Amphibians and reptiles
D. Birdsa and mammals.

Answer

**Step-by-Step Solution:**

1. **Understanding the Concept of Connecting Links:**
- Connecting links are organisms that exhibit characteristics of two different groups. They provide evidence of evolutionary transitions between these groups.

2. **Identifying Tachyglossus:**
- Tachyglossus, commonly known as the echidna or spiny anteater, is a unique mammal that has features resembling both reptiles and mammals.

3. **Analyzing the Characteristics of Tachyglossus:**
- Tachyglossus possesses certain reptilian traits, such as laying eggs (a characteristic of reptiles), while also having mammalian features like fur and mammary glands.

4. **Determining the Evolutionary Connection:**
- Given that mammals are believed to have evolved from reptiles, Tachyglossus serves as a connecting link between these two groups, illustrating the evolutionary transition.

5. **Evaluating Other Options:**
- Other potential connecting links mentioned include:
- Arcteutelix as a link between reptiles and birds.
- Sphenodon as a link between amphibians and reptiles.
- However, these do not relate to Tachyglossus.

6. **Conclusion:**
- Therefore, Tachyglossus is correctly identified as a connecting link between reptiles and mammals.

**Final Answer:**
Tachyglossus is a connecting link between reptiles and mammals.

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