Under the Mistletoe: Guided Inquiry through Collaborative Research in the Life Science Classroom

Ask your students about mistletoe and they might tell you about its use as a holiday decoration, or the custom that two people who meet under a hanging of mistletoe are obliged to kiss. We developed "Under the Mistletoe" to capitalize on student curiosity about this plant and draw learners into an engaging, inquiry-based exercise that incorporates numerous life science and biology standards in the 7th- through 12th-grade science classroom (see "About the project," p. 51). Mysterious and misunderstood mistletoe American Christmas mistletoe (Phoradendron serotinum) is a parasitic flowering plant (angiosperm) with green leaves, inconspicuous flowers, and white fruits. Described as a hemiparasite, this species of mistletoe carries out photosynthesis to make sugars, but taps into a host tree for its water and minerals. (Note: The unrelated holoparasitic mistletoe species lives on conifers in the western United States and derives all its sustenance from the host trees. This species would also make an excellent subject for study using the strategies discussed here.) The lore and mystery that surround mistletoe will serve to pique student curiosity, and its many ecological relationships offer a goldmine of potential research questions. The species is abundant in deciduous trees from Texas to New Jersey and south to Florida (Gleason and Cronquist 1991) and is easily identified in the winter months when its host trees are without leaves. Mistletoe seeds are dispersed primarily by birds, which eat the fruits and excrete the sticky seeds. Because mistletoe is easy to identify, interacts with multiple species (e.g., host trees, bird dispersers), and is something of a curiosity, it makes an excellent model system for examining host-parasite interactions and distribution patterns. Project overview Inquiry is an important element in obtaining scientific literacy in part because it demonstrates to students that science is more than just a body of facts to memorize (AAAS 1993; NRC 1996; NRC 2000; Schwartz, Lederman, and Crawford 2004). In this inquiry activity, secondary students and teachers conduct novel scientific research, from formulating the initial research question to interpreting data they have collected. In a two-part workshop held in winter and spring at Georgia Southern University, teachers receive instruction from a university scientist on how to involve 7th- through 12th-grade students in collecting real scientific data to answer an ecological research question only recently addressed by the scientific community. (Note: Teachers outside of Georgia can also participate; please see www.mistletoesite.org for more information.) By collecting data on host and nonhost tree size, location, and number of mistletoe present during the winter months--after the trees have lost their leaves--students investigate the host-parasite relationships of mistletoe, known for its use during the holiday season. If mistletoe is not abundant in your area, the research strategies can be applied to the distribution of any local plant or animal species. Students share their data through a collaborative website (www.mistletoesite.org) and use a cross-classroom database to broaden the scope of their research conclusions with regionwide data. Students gain experience developing research questions, using scientific equipment to collect data, and drawing conclusions based on the integration of math and science. Students make sense of the patterns in the data and have an opportunity to present their results to their peers and on the website (in graphical form). Participation in authentic research helps students see how the textbook facts originate from the careful processes of science and contributions of a variety of investigators. A collaborative enterprise The mistletoe project creates a learning community that involves university faculty, secondary teachers, and secondary students all working toward the same goal. …