Classify the given animal into one of these categories: mammal, fish, amphibian, reptile, or bird.
dog
The given animal, dog, is classified as a mammal.
Complete the following task based on the instruction and optional input provided.### Instruction:
Classify the given animal into one of these categories: mammal, fish, amphibian, reptile, or bird.

### Input:
dog

### Output:
The given animal, dog, is classified as a mammal.