DAYS 12-18: Setting Up Habitat and Time Lapse (5-20 min, different days)
The chrysali should remain in their pupal form for about 8-10 days. Within this time, the habitat must be set up in preparation for the emergence of the the adult butterflies.
1. Students continue to make observations of their chrysali. There will be little noticeable change during this period. (5 min)
2. While the chrysali are silently changing inside their shell, the students can be busy arranging the habitat. The teacher must provide the appropriate host plant: I used the hollyhock. Although the students do not know the identity of the butterfly species, they should research the importance of host plants to lepidopteran species. My students completed a homework assignment on host plants, and researched butterflies as bioindicators (see step #4).
3. Students should also prepare the adult butterfly food and feeders. To prepare the nectar:
Mix a 5% sugar water solution. By boiling the water, the solution will be sterilized and will last longer. Place sugar solution in a container and refrigerate until adults emerge.
The larvae should have come with feeder containers, complete with wicks. If not, students can construct feeders. Take small plastic containers with lids and punch a hole in the lid. Roll a wick made of cotton, and place it through the hole to the bottom of the container. (10 min)
4. This is also a good opportunity to discuss bioindicators. Butterflies are good bioindicators of changing/declining habitats, due to their reliance on specific plants on which they will lay their eggs. (10 min) I asked my students to complete a homework assignment on endangered butterfly species and the cause of the decline.
5. Finally, when all caterpillars have turned to chrysali, it is time to move them into the habitat. Some likely will have fallen from their webbed attachment to the cheesecloth at the top of the container. We took these poor guys and glued them to the cheesecloth with some Elmer's. Stress to the students that this must be done with care. Students may be surprised that some of the chrysali will start to squirm violently upon being touched. (20 min)
6. When the glue has dried completely, the chrysali may be placed in the test tube racks and put inside the habitats. Place the original labeled container next to its corresponding chrysali, so that students can continue to observe their own organisms:
My finger pointing to two chrysali, hanging from silk attached to cheesecloth
(Photo taken with Digital Camera)
7. We found it useful to set up a microscope aimed at a particular chrysalis and keep a careful eye on others that appeared ready to emerge. My students used the same small box, masking tape, and Velcro stage they had used for the caterpillar to chrysalis conversion. Ask the students to help brainstorm ways in which to arrive at the most effective setup -- a great lesson in creative problem solving during scientific research.
