Across
- 1. an insect with wings that is similar to a butterfly, usually flies at night
- 4. material such as coal, gas, or oil that is burned to produce heat or power.
- 7. the gradual development of something.
- 9. an animal that naturally preys on others.
- 12. a mixture of different substances or other things.
- 13. intensify, increase, or further improve the quality, value, or extent of.
Down
- 2. children or young of a particular parent or progenitor.
- 3. the dried unripe fruit grown in the plant called piper nigrum
- 5. an idea used to account for a situation or justify a course of action.
- 6. to breed or mate with a closely related individual, as in a small, closed population.
- 8. Science that studies religions
- 10. Structural element of a tree
- 11. a group of animals related by descent