Across
- 4. ________ of the fittest
- 5. The environment
- 7. How species have changed over time
- 9. The existence of a human being or animal
- 10. A flying animal
Down
- 1. When a species dies out
- 2. Invented the theory of Natural Selection
- 3. group of islands which contain a large variety of animals
- 6. mammals, marsupials, etc
- 8. An idea that is used to explain an event