science

In this hands-on, minds-on activity, students analyze the similarities and differences between bat and squirrel skeletons and between bat and insect wings.

Students learn about the two ways that evolution produces similarities: (1) inheritance from shared evolutionary ancestors (homologous characteristics) and (2) independent evolution of similar characteristics to accomplish the same function (analogous characteristics).

In the laboratory investigation, students observe the external anatomy and locomotion of earthworms, mealworms, and crickets. Students use these observations and the concepts they have learned to figure out which two of these animals are more closely related evolutionarily. (NGSS)

Download Student Handout: PDF format or Word format

Download Teacher Preparation Notes: PDF format or Word format

To begin this hands-on, minds-on activity, students view a video about ecosystem changes that resulted when wolves were reintroduced to Yellowstone. Then, students learn about food chains and food webs, and they construct and analyze a food web for Yellowstone National Park. Students use what they have learned to understand trophic cascades caused by the return of wolves to Yellowstone.

Next, students learn that the biosphere requires a continuous inflow of energy, but does not need an inflow of carbon atoms. To understand why, students analyze how the carbon cycle and energy flow through ecosystems result from photosynthesis, biosynthesis, cellular respiration, and the trophic relationships in food webs.

In the final section, students use the concepts they have learned to understand trophic pyramids and phenomena such as the relative population sizes for wolves vs. elk in Yellowstone. Thus, students learn how important ecological phenomena result from processes at the molecular, cellular, and organismal levels.

For virtual instruction, you can use Food Webs – Understanding What Happened When Wolves Returned to Yellowstone, Carbon Cycles and Energy Flow through Ecosystems and the Biosphere, and Trophic Pyramids. 

Most of our activities for helping middle school and high school students learn life sciences are aligned with the Next Generation Science Standards (NGSS; http://www.nextgenscience.org/next-generation-science-standards and http://www.nextgenscience.org/sites/default/files/HS%20LS%20topics%20combined%206.13.13.pdf). The attached tables summarize our activities that are explicitly aligned with NGSS Disciplinary Core Ideas and Performance Expectations. These tables also summarize how each of these activities engages students in Scientific Practices and provides the opportunity to discuss Crosscutting Concepts. Brief descriptions of these activities are compiled at /exchange/bioactivities/NGSS/listing. The Teacher Notes for each activity provide additional information concerning alignment with the Next Generation Science Standards.