Satellite observations coupled with ecosystem models suggest that the decline in Arctic sea ice has led to an increase in ocean algae across the region and a decline in sea ice algae in parts of the Arctic. To predict how shifts at the base of the Arctic food web may affect other organisms, scientists seek to better understand Arctic feeding relationships by studying fat molecules. Scientists have discovered that ocean and sea ice algae make different types of carbon-based fats. Why does this matter? Well, these carbon-based fats are transferred to animals when algae are eaten, all the way up to polar bears and bowhead whales. Scientists have been able to measure the amount and type (ocean algae vs. sea ice algae) of carbon-based fat in Arctic animals to determine whether the animal's diet is more dependent upon ocean algae or sea ice algae.
Context for Use
What Students Will Do
- Trace the flow of energy through the Arctic food web by analyzing and interpreting carbon-based fats (ocean vs. sea ice algae) stored in Arctic animals.
- Construct conceptual models to explain how the decline sea ice may affect the Arctic food web.
Part 1 (20 minutes) Eliciting Students' Ideas
- Students explore the opening scenario prompt, "You are what you eat" through a video and whole-class discussion.
Part 2 (40 minutes) Identifying Important Science Ideas
- Students engage with an interactive reading to 1) identify similarities between the opening scenario prompt and the work of Arctic ecologists studying the Arctic food web, and 2) make predictions as it relates to the investigative question, "How might the decline in sea ice affect Arctic organisms large and small?"
Part 3 (30 minutes) Supporting Ongoing Changes in Thinking
- Students test their prediction about the changing Arctic food web by tracing the flow of carbon-based fats through the food web (from producer to tertiary consumer).
Part 4 (30 minutes) Constructing Evidence-Based Explanations
- Students reflect on evidence gathered during parts 1-3 and construct a final explanatory model for the question, "How might the decline in sea ice affect Arctic organisms large and small?"