We're Emily and Julie and we are crazy about butterflies! We decided to take a trip to the Butterfly House at the North Carolina Museum of Life Sciences. While we were there we saw lots of different kinds of butterflies including a Blue Morpho. The Blue Morpho has wings that are able to change color between blue and green. Our question: How is a Blue Morpho butterfly able to change the color of its wings?
What did we do?
First we talked to Leon, he's an entomologist at the museum. Leon explained that butterflies get there color one of two ways--either through pigment or through iridescence. The Blue Morpho gets its color from iridescence, giving off two different colors depending on how you look at it. Leon explained that iridescence can be found in things like soap bubbles and oil slicks, so we decided to try it for ourselves! After playing with some soap bubbles we met up with Fred at Duke University to figure out how exactly the iridescence in a butterfly wing and the iridescence in a soap bubble were related. Fred suggested that we try a color test at home to see which butterfly wings contained pigment and which contained iridescence. We did this by dropping some acetone onto different wings and observing if any change occurred.
What did we find out?
We discovered that iridescence had something to do with the thickness of the object (like the bubbles). We saw that the thinner part of the bubble contained almost no iridescence while the thicker part became a swirl of colors. After talking to Fred we learned that this is due to structure of the object. A butterfly wing is made up of many scales and in between each scale is an air pocket where lots of tiny holes (like bubbles) were all lined up together--this is where the iridescence came from! The color test we performed at home showed that some butterflies have pigment, some have iridescence and some have both.
- Have a Bubble Party and experiment with new ways to make bubbles! Dip the wide end of a funnel into a bubble solution and blow through the narrow end. Blow a mass of bubbles by dipping a tea strainer into a bubble solution. Dip a straw into a bubble solution and blow slowly. Who can create the biggest bubble?
- Recycle your leftover bits of soap to create a lasting jar of bubble mix. Just rinse off the soap ends and put them in a jar with some water and close the lid. Keep adding on to create a never ending bubble solution supply!
- Welcome colorful butterflies to your house! Label 3 dishes that contain: plain water, sugar water and salt water. Place them outside and start your butterfly watch. Which dish attracts the most butterflies? How many different types of butterflies visited your house?
- Have a peacock feather lying around? If not, you can get them at a local craft store. Some colors (especially the blue) change depending on how you look at them. Try tilting the feather to see this in action. What happens when you place a drop of water on that part of the feather? Does it look different after the water dries?