Across
- 3. A species perishing or evolving out of existence
- 5. The origin of life
- 7. Age of the Earth, in billions of years, to the closest integer
- 9. Early life's favorite soup
- 10. Variety of Earth's life
- 11. Describes molecules containing carbon
Down
- 1. Modern cell's hereditary molecule
- 2. Earliest genetic molecule
- 3. Cell type with nucleus, evolved from prokaryotes
- 4. Reproductive success in natural selection
- 6. Base unit of life
- 8. Something that makes an organism more suited to an environment