Duck billed platypus is a connecting link between

Options

A. Reptiles and mammals
B. Reptiles and birds
C. Fishes and amphibians
D. Amphibians and reptiles

Answer

**Step-by-Step Solution:**

1. **Identify the Duck-Billed Platypus**: The duck-billed platypus, scientifically known as Ornithorhynchus, is a unique animal that exhibits characteristics of both mammals and reptiles.

2. **Examine Mammalian Characteristics**: The duck-billed platypus displays several traits typical of mammals, including:
- **Mammary Glands**: It produces milk to feed its young.
- **Hair**: It has hair on its body, which is a characteristic feature of mammals.
- **Diaphragm**: The presence of a diaphragm aids in respiration.
- **Single Aortic Arc**: Unlike reptiles, which typically have a different arrangement of aortic arches, the platypus has a single aortic arch.

3. **Examine Reptilian Characteristics**: In addition to its mammalian traits, the duck-billed platypus also has some reptilian features:
- **Large Coracoid in Pectoral Girdle**: This is a characteristic of reptiles.
- **Egg-Laying**: The platypus lays eggs that have yolk and a shell, similar to reptiles.

4. **Conclusion**: Based on the presence of both mammalian and reptilian characteristics, the duck-billed platypus serves as a connecting link between reptiles and mammals.

**Final Answer**: The duck-billed platypus is a connecting link between reptiles and mammals.

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