Module 5 Human Dimensions in the Poles
This unit covers the concept of bioaccumulation of contaminants in a food web, all the way up to humans. Students learn about what constitutes a contaminant, how contaminants can accumulate in an organism and move up the food web, and how people who consume animals near the top of the food web can then accumulate contaminants within themselves. To demonstrate this, students will read about heavy metal contamination in polar marine animals, and about metal contamination in the people who rely on hunting these animals for food. By bringing in this human element, students will better empathize with how pollution can impact people even if they live nowhere near the source of pollution.
- Students will be able to describe pollution
- Students will be able to describe how contaminants become more concentrated further up the food chain
- Students will gain an appreciation for how humans are affected by polluted animals
- Students will compose a thoughtful letter-to-the-editor based on scientific data they find, analyze, and interpret
Context for Use
This unit is designed to be taught to undergraduate non-science majors over several 75-minute class periods as part of an introductory marine science course, where students discuss a news article, have a lecture, complete a pair programming exercise with the aid of instructional videos, and conclude with an opportunity to write a response to the author of the news article read at the beginning of the unit.
If adapting this entire course, students will practice what they've learned in the first two modules, as well as expand on the impacts of what they learned in the third module. They will need to use their narrative interpretation skills as well as their R plotting skills to visualize data and draw conclusions. If this is not being taught after the previous module, then it will need to be adapted.
Some initial time should be spent summarizing the concepts of the previous modules so that students have at least a general understanding of the sorts of animals that can be found in the Arctic, and thus what is available for people to eat.
Description and Teaching Materials
The first few minutes of class should be spent discussing students' thoughts on the news article, and what they thought the heroes, villains, problems, and solutions were. The handout includes several questions on it which can guide how students should be thinking about the article and data as they move forward. Following this, the lecture can be given to introduce students to the key properties of the module. This can be done in the same class period or may be spaced out over several class periods to limit the time spent lecturing in any class period. Additionally, the lecture can be removed entirely and replaced with another method of information dissemination, such as an in-class reading. After the lecture, students can watch the two R coding videos for the section and follow along, creating their own R code.
Example lecture topics for this module include:
- DDT, Dioxins, PCBs, TBT, Metals, Plastics, Oil
- Climate change-induced opportunities for polar extraction/use
- Native health
- Diet and culture
- Links to wildlife health
The instructor should be ready to provide technical support and assist students if they become confused or lost. This module contains two instructional videos, and it is intended that each video is allotted one class period for students to watch it and for the instructor to aid as students make their code. If students do not complete their code in class, it becomes homework. Students will generate graphs in R, and these can be submitted at the beginning of the next class period for a few points, creating a low-impact assessment that encourages students to stay engaged in the class.
After the videos have finished and students have generated their graphs, the discussion can return to the article to see if students have different viewpoints after looking at the data themselves. This can occur at the end of the class period after watching the second R video or can happen the following class period. The questions on the handout can help facilitate this discussion, and students should now be able to answer all the questions on the sheet except for the last one which requires work outside of class.
Students should then spend time at home finding more data they can analyze that is related to the news story and pen a letter to the editor to respond thoughtfully to the news article. This letter should include graphs of the data covered in class and other data the student finds on their own (see example at right). This serves as the primary assessment for the module, as the letter will show students' grasp of what the article says, what the data says, and demonstrate the students' ability to critically analyze and draw conclusions from both.
- Module handout with questions (Microsoft Word 2007 (.docx) 196kB Dec31 19)
- R Tutorial Videos and Data
- Elements of a Story form (Microsoft Word 2007 (.docx) 12kB Dec29 19)
- News article from Nunatsiaq Online (Acrobat (PDF) 364kB Dec31 19)
- Journal article by Chan et al. from Environmental Health Perspectives (Acrobat (PDF) 2.1MB Dec31 19)
- Inuit Health Survey Website
Teaching Notes and Tips
The lecture and assigned textbook readings help students gain an understanding of the scientific concepts behind the data presented in the module. However, an in-depth understanding of these factors is not necessary to interact with the news article and data, and thus both may be eliminated to save time if desired. Alternatively, the material covered in the lecture and textbook may be expanded on to create a longer course on polar science.
Students are still likely to struggle with the heroes, villains, problems, and solutions of the article, so they will need help during the class discussion to ensure everyone understands. While it is best if the students can work through the details as a class, they may need some guiding questions from the instructor to help them reach the correct conclusions. One way to go about this is to first have students list off all the people and things discussed in the article, then categorize them into good, bad, or neutral as presented by the article.
Unlike the previous modules, the data for this unit comes from a scientific paper rather than an online database. The data has already been digitized and should be distributed to the students to save time and possible errors from entering the data into Excel spreadsheets.
With the R code, if students follow along with the video, they should have little trouble. Where students may struggle is when asked to find their own data sets. This can be particularly daunting for students who have never had to seek out data before. These students may need extra attention and assistance to become accustomed to how to seek out new data sources. An alternative option is for the instructor to provide several suggested data sets for students to access and analyze, as this eliminates the need for students to search for new data but still requires them to choose a data set and work through it on their own.
As students work through the code for the two videos, they will generate several R plots. Having students submit these at the start of the next class provides further motivation to keep pace during class, and anything they do not finish in class they then finish at home.
The letter-to-the-editor (Example Rubric (Acrobat (PDF) 289kB Jan8 20)) is the product that tests understanding of both the news article and the data set analyzed. It goes a step further by having students bring in an additional data set to their discussion, ensuring that students are not just parroting back concepts learned in class but are actively applying them to something not directly worked through in class.
If this course is taught in its entirety, this is the final module of the core course. As a result, on the last class period, the post-test can be administered. This is identical to the pre-test given in the first class period and is an excellent way to check how understanding of the concepts covered has improved over the course. This can be given on paper or distributed through an LMS. If the optional module is included, then the post-test can be given at the end of that module instead.
References and Resources
- Morrissey et al. Intro to the Biology of Marine Life (Chapters 5.2, 8.3, 8.4, 9.5, 15)
- Murphy, D. "High mercury levels prompt health advisory in Nunavut" Nuntatsiaq Online, June 29, 2012 (http://www.nunatsiaqonline.ca/stories/article/65674high_mercury_levels_prompt_health_advisory_in_nunavut/)
- Data: Chan et al., 1995. Assessment of Dietary Exposure to Trace Metals in Baffin Inuit Food, Environmental Health Perspectives, 103 (7-8) pp 740-746. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1522199/pdf/envhper00356-0109.pdf)
- R Core Team. 2017. R: A language and environment for statistical computing. Vienna, Austria. URL https://www.R-project.org/
R code files (for instructor reference only)