Across
- 1. Birds lay ... ?
- 5. Animals that are born alive and drink milk from their mothers.
- 6. Birds are covered in ... ?
- 8. Humans are covered in ...?
Down
- 2. Animals that live in water breathe through this.
- 3. Fish have this instead of skin.
- 4. Animals that live both on land and in water.
- 6. Most mammals are covered in ...?
- 7. Birds fly thanks to their ...?