Across
- 1. In poison dart frogs, bright blue colors broadcast a warning to predators that the animal is _______
- 3. A material that produces a color depending on which wavelengths of visible light it absorbs and which it reflects
- 4. A blue mineral mentioned in the article
- 7. A synonym for rare, used in the first paragraph of the article
- 11. the type of light visible at 400 nanometers
- 12. The subject of this article
- 14. The vivid blue pigment ground from lapis lazuli
- 16. The highest points on a wave
- 17. A blue flower mentioned in the article
- 18. The lowest points on a wave
- 19. Blue animals' colors rely on ______ to create a blue appearance
Down
- 2. each of our eyes contains between 6 million and 7 million light-sensitive cells called ________
- 5. platypus fur glows in vivid shades of blue and green when exposed to ______ rays, a form of light not visible to the human eye
- 6. The cornflower absorbs this color
- 8. the distance between two of the highest points or two of the lowest points on a wave
- 9. Light that we do not see is absorbed off of objects, while light that we do see _______ off of objects
- 10. The earliest use of blue dye was recorded in this country
- 13. Light is a form of energy that travels in ______
- 15. Known as the blue planet