Name two animals which are not mammals.
Two animals which are not mammals are: 

1. Reptiles, for example: a crocodile.
2. Birds, for example: an ostrich.
Complete the following task based on the instruction and optional input provided.### Instruction:
Name two animals which are not mammals.

### Output:
Two animals which are not mammals are: 

1. Reptiles, for example: a crocodile.
2. Birds, for example: an ostrich.