Lifecycles of Butterflies
Lesson 7
From Caterpillar to Chrysalis
Students learn that butterflies have a life cycle.
3. Lesson set up and Management
Understand characteristics of living organisms- identify observable characteristics of living organisms (Concepts and Principles 1-1.1.6)
Understand that plants and animals have life cycles- observe and describe the life cycle of a plant or animal (Systems 1-1.2.7)
Butterflies have a life cycle and change with each stage.
3. Lesson set up and Management
Materials:
For this lesson, students again need the caterpillars or chrysalises in the cups and hand lenses for observation. Activity Sheet 6, What Happens to the Caterpillars? will need to be copied if it is to be used.
The flight cages will need to be assembled and a paper towel put in the bottom. Some people like to put transparency or wax paper in the bottom of the flight cage to make them easy to clean. Twigs can also be put into the flight cages.
The flight cages are in the kits but sometimes it is difficult to get good views of the butterflies in them. A glass terrarium is a good alternative, as is the hanging cage in Appendix C, page 106, Figure C-2 (Teacher Guide 2002 Version).
Net flight cage
Individual flight cages can be made by using a tuna fish can or a jar lid and wire mesh screen. Snip the mesh screen to make a cylinder to fit into the can or lid. Put another can or lid over the top of the mesh cylinder.
If using the provided flight cages, an adult needs to assemble them. When attaching the chrysalis in the flight cage, tape the whole tissue to the sides of the terrarium or flight cages. Sometimes, if using a net flight cage, a toothpick can be used to attach the tissue to the netting.
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An egg carton can hold chrysalis lids. |
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Procedure:
Caterpillars can and will develop and transform at different rates and students should observe each other's caterpillars. Students will observe the caterpillars in whichever phase they are. It is possible to see the caterpillar form a j-shape as it hangs by a silk button on the lid (or tissue). When this is observed, the caterpillars should be watched closely as it only takes a few hours for them to form the chrysalis.
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Caterpillar beginning to form a chrysalis. |
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Throughout this unit students are asked to predict. This is a WASL expectation and it is not too early to start students thinking about using nouns in their predictions rather than pronouns like "it". Some students may be ready to add a "because" phrase to explain their prediction.
Detached caterpillars often do not develop properly. Students often feel bad when this happens. It is a good idea to give an extra chrysalis to these students.
Background Information The caterpillar is about to enter the third stage of the life cycle. This is the pupa stage, also called the chrysalis. While in the chrysalis stage, the caterpillar's body changes into the butterfly body. It forms four wings and flight muscles as well as the three distinctive body parts: head thorax, abdomen. It also forms the nectar-sucking organ called the proboscis in place of the leaf chewing jaw it had before.
Right before the formation of the chrysalis, the caterpillar will attach itself to the lid of the cup with a silk button. There it hangs upside down and forms a j-shape. When this happens, watch carefully for the chrysalis to form. This will happen in a matter of hours.
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Newly formed chrysalises. |
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Writing Support:
No writing support for this lesson.
Reading Support:
Judith Viorst's The Tenth Good Thing About Barney is a sensitive story about Barney and how everyone acted and felt when he died. This story portrays death as a natural part of life.