This investigative case module was prepared as part of a BioQUEST faculty development workshop. The cases, resources, and implementation strategies were developed by participants for use with their own students. We invite you to adopt and adapt the following materials.

The BioQUEST Curriculum Consortium is committed to the reform of undergraduate biology instruction through an emphasis on engaging students in realistic scientific practices. This approach is sometimes characterized as an inquiry driven approach and is captured in BioQUEST's three P's (problem-posing, problem-solving, and peer-persuasion). As part of this workshop groups of faculty were encouraged to initiate innovative curricular projects. We are sharing these works in progress in the hope that they will stimulate further exploration, collaboration and development. Please see the following links for additional information:

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Investigative Cases
The Case: Java Water

The DEQ reports that the Willamette River contains measurable levels of caffeine. Water samples were taken from Harrisburg, downstream from the Eugene water treatment plant and upstream from the city of Corvallis water intake facility. Data indicates the caffeine levels are increasing from year to year.

Local fishing groups are concerned about the potential impact upon food species for migrating salmon fry. "The caffeine may make them get to the sea faster, but if it kills their food sources then they are going to be awful hungry when they get there" stated an anonymous official.

Case Author:
Stacey Kiser Lane Community College

Case Analysis

How does caffeine get into rivers?
What do salmon fry eat?
What types of salmon fry food species live in this part of the Willamette River?
What are the effects of caffeine on the food species? On the fry?
Should we do anything about caffeine in our river?
Have students fill out a table like the one below:

Option: Include a know / need to know chart like the one below:

What do you know?
What do you need to know?

Learning Goals


Identify field-collected invertebrates (at least to phylum)
Describe physiological differences and similarities across the invertebrate phyla in selected organism system/systems.
Summarize and report potential impacts of a new environmental pollutant (caffeine) to an authority.



Investigations and Activities

Collect and identify potential salmon fry food species in the Willamette River.

Potential link to chemistry: Measure caffeine levels in Willamette River from water samples (or in Lane CC sewage lagoons).

Study effects of caffeine on California Blackworm (Lumbriculus variegatus) and water flea (Daphnia spp.)

Study effects of caffeine on California Blackworm (Lumbriculus variegatus) and water flea (Daphnia spp.)

Write preliminary report on the affects of caffeine on salmon fry food species to local city regulatory board.



Web sites:
1995 Report on Mississippi River caffeine levels:

General report on caffeine (unknown effects)

Potential NPR audiofile:

Industry source:

Lumbriculus variegatus information and potential labs:
Daphnia information page:
maps, etc.

Students will usually obtain additional references or resources
to help answer or explore their questions.

Special Data Items

1. daphnia.JPG
2. river.JPG
3. javamap.JPG
4. worm.JPG
5. javafolks.JPG


Student Products

Field notebook from collection field trip, including identification of organisms.
Laboratory report on effects of caffeine on invertebrates.
Report to regulatory board with adequate research support.

Assessment and Evaluation Plan

30 % Field notebook and identification of sample organisms.
30 % Laboratory report on effects of caffeine on invertebrates.
40% Report to authorities.



Course name:
General Zoology - Invertebrates
Likely sequence in syllabus:
Capstone activity to quarter of invertebrate diversity and comparative physiology.
Time during term:
End of the term.
1.5 weeks (9 classroom hours).
Field and lab
Students in course:
Freshmen/Sophomore Majors
Collaborative elements:
Working in groups, sharing resources, group meetings outside of class, group report writing
Additional notes:



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