Testing for Grazer Adaptation to Toxic Algae
Department of Ecology and Evolutionary Biology
University of Connecticut: Avery Point Campus
Department of Marine Sciences
University of Connecticut
Department of Arts and Sciences
Maine Maritime Academy
The intent of this interrupted case study is to present a clear example of both the scientific method and evolutionary adaptation in a model system consisting of marine grazers (copepods) and toxic prey (phytoplankton). Briefly, a certain toxic phytoplankton is found only north of Long Island Sound in the United States; however, populations of their copepod grazers are found more extensively from Maine to Delaware. Students will consider whether exposure to toxic phytoplankton among northern grazer populations has led to greater fitness compared to those populations that have never experienced the toxin (i.e., southern populations), and whether the evidence supports adaptation or plasticity. Students will also discuss the broader impacts of adaptation to toxins in marine food webs. A primary aim is to show students how to go from observation and hypothesis to analysis of data. This activity was originally designed for a second year evolutionary biology or ecology course, but can easily be adapted for the evolution section of a general biology course or an upper-level biological oceanography course.
- Understand how a set of observations leads to an important and testable scientific question.
- Generate a testable hypothesis.
- Develop a detailed experimental methodology to test the hypothesis, with emphasis on controls.
- Determine if the results presented in the case study support the hypothesis, and why.
- Identify how answering the question (i.e., testing and supporting the hypothesis) leads to additional related scientific questions.
Keywordsevolution; toxic algae; common garden; food web; copepods; Long Island Sound; paralytic shellfish toxins; PST; harmful algal blooms; HAB; nitrogen; nutrients; phosphorus; red tides
Topical AreasScientific argumentation
Educational LevelUndergraduate lower division, Undergraduate upper division
Type / MethodsInterrupted
Subject HeadingsBiology (General) | Ecology | Evolutionary Biology | Science (General) | Marine Science / Oceanography |
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This optional material from Science Friday provides another nice example of rapid adaptation by a fish.How Lake Fish Are Coping With Pollution
Can The Great Lakes Stay Great?
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The following video(s) are recommended for use in association with this case study.
- The Origin of Species: The Beak of the Finch
This video from HHMI on the Galapagos Finches provides a great example of natural selection and adaptation and can serve as a useful introduction to this case study. Running time: 16:08 min. Produced by HHMI BioInteractive, 2014.