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Activity: What happens when a food web is disturbed?

Make science come alive in your classroom with this free hands-on activity aligned to middle school NGSS standards.

Activity: What happens when a food web is disturbed?

A polar bear trudges through a bleak landscape in the Arctic. There is nothing in sight except for ice. So, what does this polar bear eat to survive? The answer is found below the ice. Despite the cold, the Arctic is filled with life!
In this activity, students explore the Arctic marine food web in order to understand how energy and matter are transferred between different organisms. Students then use their understanding to hypothesize how the Arctic marine food web will change after a disturbance.
A male polar bear walks through an Arctic landscape of ice and patches of sea water.
This male polar bear failed to catch a bearded seal and is on his way to find another prey. Image credit: "Polar bear after unlucky hunt for a seal" by Andreas Weith, under CC BY-SA 4.0.

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This activity is designed to be completed in two 45-minute class periods, with additional time required for follow-up creative projects. The activity consists of the following parts:
  • Setting the stage—Students read and demonstrate understanding of organisms found in the Arctic marine ecosystem and their roles in the food web. (10 minutes)
  • Investigation (Part 1)—Students model the Arctic marine food web to illustrate the many connections of energy and matter from one organism to the next. (20 minutes)
  • Investigation (Part 2)—Students learn about a disturbance to a food web. Students then predict how such a disturbance can impact the population size of different organisms. (15 minutes)
  • Let's get creative!—Students research how climate change is affecting a focal organism from the Arctic marine food web. Students then imagine that they are leading a research team—they develop predictions and research questions about how climate change might disturb their focal organism and its connections to other organisms. (45 minutes)
  • Keep creating!—Students can choose from additional project ideas. Each project encourages students to combine scientific knowledge with creativity to produce something new.

NGSS performance expectations

MS-LS2-3. Develop a model to describe the cycling of matter and flow of energy among living and nonliving parts of an ecosystem.

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