Teaching activity: Bioaccumulation in the sea

The following steps direct attention to how the model communicates complex ideas in simple terms. 

1. Ask students to explain how the model communicates

• what eats what. (The click and drag is rejected if a link is not correct.)
• the presence and amount of the toxin. (A red dot represents actual presence; the more red dots the more toxin is present.)
• the differences in overall toxin accumulation. (The number of red dots that can accumulate in total represents the comparative amount of toxin that builds up.)

2. Ask students to use this knowledge of how the model works to explain which species would seem to be most at risk from bioaccumulation of this toxin? (To do this they will need to compare dots accumulated per feeding interaction.)

3. Ask students:

• How does this model simplify the idea of bioaccumulation so it can be more easily understood? (For example, what does the model leave out? Would a static model work as well?)
• What sort of information would scientists need to gather before they could build a model such as this one? (Actual quantitative data about rates of accumulation in different species, probably using bioassay techniques, which are discussed elsewhere in the Toxins resources on the Science Learning Hub.)
• How would scientists represent this work to an audience of their peers? (Probably in a refereed journal article, with full details of the methodology, data gathered and analysis techniques.)

4. You could then discuss possible “costs” of glossing over the extent and complexity of the scientific research that sits behind any model that simplifies science ideas to communicate them to a non-expert audience. (For example, almost every aspect that would build other scientists’ trust in the ideas about bioaccumulation in this marine environment is missing in the model. There is no option but to take the model on trust (or perhaps reject it because you don’t “believe in it”) unless you know how to develop critical questions about the underlying science and then search elsewhere for answers to these.)

5. Literacy extra: Consigning a whole complex process to one noun, based on a related verb, is a feature of science texts. The name given to this grammatical feature is nominalization. Students could think about other examples and how much “unpacking” is needed to really explain the process that they signal (For example, evaporation, crystallization, sublimation, respiration, carbon sequestration, subduction – the list is almost endless.)

Scientists represent their ideas in a variety of ways, including models, graphs, charts, diagrams and written texts. Understanding the role that modelling can play conveying science explanations is an important aspect of building science literacy. Students need to appreciate that models are not just fanciful guesses but rather are based on the best theoretical thinking available to scientists at the time. They also need to understand that models are highly selective representations: their explanatory power often rests as much on what they leave out as on what they include.

What are we looking for?

Can students describe the specific communication strategies built into the interactive model?

Do they appreciate that, even though the model is very simple, it conveys quite complex science ideas, including basic quantitative comparisons, based on actual scientific research?

There are a number of interactive resources on the Science Learning Hub Pokapū Akoranga Pūtaiao and many more elsewhere on the internet. However only some have been designed for the explicit purpose of communicating a concept (many simply convey information). Any that do use interactivity to enhance conceptual understanding this could be critiqued in the same way as this example. For example, Who’s for dinner? is a simple game that models the complex principles of ecological energetics.

Support material in the Assessment Resource Banks collection includes further ideas about nominalisation and other aspects that make science text challenging to read and understand:

Language of Science (Specialised Language): Nominalisation

More general features of science writing are explored in the resource National survey of garden birds.

Teaching activity: The Modified Mercalli intensity scale (L5) GNS Science