Book 4, Question 47
Why Do Flies Have Compound Eyes?
A compound eye is a bundle of tiny lenses! Together, they make a wide, fast picture. So a fly can spot a swat coming from the side.
From the book
Page from A Million Whys Book 4
More fun facts
- A compound eye is made of many tiny seeing units, sometimes hundreds or thousands.
- Each unit sees a small piece of the view, and the pieces combine like pixels in a picture.
- Compound eyes keep things in focus whether they are near or far.
- A dragonfly's two big eyes each have about 30,000 facets pointing in slightly different directions.
- Spiders have eyes more like ours than like a fly's.
- Some clams and sea stars have compound eyes too.
- Engineers built a camera that copies insect compound eyes.
Sources: Science News Explores, National Geographic, National Park Service
Questions kids ask
What does a fly see?
Its eyes put together many tiny views, like pixels, into one picture.