In a recent video, we dissected a roast chicken, seeing how the muscles connected to bones to power its wings. This time, we are going to explore a very different arrangement for flight by examining the flight of insects. To try this, you will need: - 2 popsicle sticks or tongue depressors - a hollow, rubber ball - a sharp knife - an adult to use the shape knife (Adults are easier to bandage if they cut themselves.)
Lets start by thinking about bird wings. As we saw in the Bird Bones video, they are made up of several bones, connected at joints, and powered by muscles. An insect's wings are very different. Each wing is all one piece, made of chiton, the same substance that makes its exoskeleton. The wings do not have any joints or muscles. So how do they move?
We can see that by constructing a model, a representation of the insect that will help us understand what is happening. Sometimes scientists use computer models, developing computer programs to simulate a specific event. Other times they construct models from materials to allow them to test ideas. That is what we will do. You need a rubber ball that is hollow, not solid rubber. You can find these in the toy department in many stores. Pick a point on the ball and carefully use the knife to make a cut that is about as long as your popsicle stick is wide. Carefully, insert the end of a popsicle stick into the cut.
Looking at the ball, imagine the face of a clock. Turn the ball until the stick is about at 2:00 on the imaginary clock face. Then make a mark on the ball at about the 10:00 point. Make another cut there, and insert the other stick. Your model butterfly is now complete.
The ball represents the body of the insect. Instead of having muscles attached directly to their wings, most insects move their wings by changing the shape of their bodies. Muscles attach to the top and bottom of the body. Contracting those muscles flattens the body, causing the wings to move up. You can see that by squeezing the ball from top to bottom.
By relaxing those muscles and contracting others, the body changes shape again, moving the wings downwards. You can see that relaxing the hand that is squeezing top to bottom, and instead squeezing the ball from side to side. As the insect flies, its body is flexed by muscles, causing the wings to move up and down. By controlling how much each set of muscles contracts, the insect can change the movement of its wings to control its flight.

This method of flight is used by most insects, including bees, wasps, flies, butterflies, and moths. There are a few insects, most notably Dragonflies and Damselflies, that do have muscles attached to the base of their wings. This lets them control each wing independently, making them very agile fliers.

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This week's experiment is a result of preparing for next week's experiment. It began as an experiment with insects, but it was getting too long, so I chopped it in half. (The experiment, not the insect.) This week, we will look at the amazing variety of insects that can be found almost everywhere.

The first thing to do is to carefully examine the bushes. You want to be sure not to disturb a nest of wasps or bees. Also check for bird nests. Since this experiment is not about the birds and the bees, we want to be sure that we don't bother them and they don't bother us.

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This week's activity is one that I use for Schoolyard Ecology workshops. It is a great warm up for getting people to slow down and really look at the world around them. To try this, you will need:

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The idea for this week's experiment comes from my wife, Nancy. I was sitting here at the computer, trying to decide what to write about when Nancy made a comment about how good the flowers on the table smelled. Nancy loves flowers, and always has lots of them around the house. That one whiff and this week's newsletter practically wrote itself.

If you are lucky enough to have flowers around your house, take a few minutes and smell them. If you don't have flowers around the house, you should be able to find a variety of flowers at your local grocery, hardware store, or nursery. Once you are surrounded by the flowers, take the time to sniff them, one by one. Keep track of your observations (sniffservations?) What did you notice?

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This week's experiment is a result of preparing for next week's experiment. It began as an experiment with insects, but it was getting too long, so I chopped it in half. (The experiment, not the insect.) This week, we will look at the amazing variety of insects that can be found almost everywhere.

You will need:
- an umbrella
- a magnifying glass
- some shrubs or bushes

The first thing to do is to carefully examine the bushes. You want to be sure not to disturb a nest of wasps or bees. Also check for bird nests. Since this experiment is not about the birds and the bees, we want to be sure that we don't bother them and they don't bother us.

Next, open the umbrella. Hold it upside down, so that it hangs down from your hand instead of being over your head. Hold the umbrella under one side of the bush. With your other hand, grab the bush and give it a good shake. Now you know why we checked for bees. It is hard to do science experiments while you are running from an angry bee. The bowl shape of the upside down umbrella makes a perfect way to catch falling creatures. After a few good shakes, you should have some leaves, but you should also have quite a few other things. Place the umbrella on the ground and grab your magnifying glass.

Depending on where you live, what the season is and which bush you picked, you probably got several kinds of insects. I say insects, not bugs, because while bugs are insects, not all insects are bugs. Bugs are a specific group. Their mouth is a long, sharp tube, like a drinking straw. Most of them feed on plant juices, so you probably have some bugs in your umbrella, but you probably have insects from other groups too.

You may also have collected spiders, lizards, frogs, or other creatures. Examine them carefully. We don't want to hurt them, and we don't want to disturb any that might bite you. As you examine your catch, you may want to write down notes, draw pictures or take photographs to help you keep track of what you found.

When you are done, tip the umbrella over the bush to put them back where they belong. Then move to another bush and try it. You will find that the insects and other creatures will vary from bush to bush. Different kinds of bushes are eaten by different kinds of insects. Even with the same kind of bush, location makes a difference. You will probably get different things from a bush in the sun than you do from a bush in the shade.

When you are finished, be sure to tip the creatures back into their bush. If you put them on the wrong bush, they might not find anything to eat. If you forget to put them back, the next time it rains, you may get quite a surprise when you open your umbrella.