Teaching Ecology by Inquiry

What is inquiry? Is it hands-on activities? Is it the major task or lab at the end of a unit? For me, inquiry is a process where we use questions, observations, and evidence to build our understanding. Inquiry is something that we do every day; it is a fundamental part of the way we learn. What does that look like for the topic of ecology? Let's find out! I have been revising my ecology lessons for the new curriculum and would like to bring you on a little tour.

The big questions of inquiry

There are two questions that I have in mind when I design an inquiry lesson:

(1) How did people ever figure this stuff out?

(2) How do people use this knowledge?

These questions help me decide what to include in a lesson. I want students to examine real scientific data and collect some of their own. I want students to look at the scientific work of ecologists and appreciate the questions they ask and the work they do. All of this helps expand our understanding of the natural world and the role of humans in it. I will highlight these points as we explore each lesson.

Lesson 1: Exploring Our Ecosystem

Activity = quadrat sampling Ideas = factors affecting biodiversity

We start with an outdoor exploration of our schoolyard ecosystem using quadrat sampling. This is a common ecology activity, but what is important is how we frame its purpose. For a teacher, the purpose might be getting the students active and out of the classroom as a change of pace. But for an ecologist, there is always a scientific question that guides or motivates the exploration. An ecologist doesn't run out into a field and start counting organisms just for the fun of it (that’s what grad students are for)! In our investigation, we want to examine the amount of biodiversity in different regions of the schoolyard and relate that to the biotic and abiotic factors of that area. In an inquiry-based unit on ecology, this is an important feature: our scientific activities are guided by questions and are linked to other scientific knowledge. This helps make the learning task more meaningful both scientifically and pedagogically.

Part of our methodology for quadrat sampling involves identifying plants. Students carry a white background to photograph the plants against and use the website https://identify.plantnet.org/ to identify the plants.

They do their best counting or estimating the number of each plant and record the results in a Google Sheet. These results seed our class discussions that relate the observed biodiversity to biotic and abiotic factors of that area. I like how this lesson both introduces a core idea for the unit, biodiversity, and introduces the fact that ecology is a mathematical discipline! Actual work by ecologists often relies heavily on statistics and data representation techniques. Actual ecology students are often shocked in university when they are required to learn more math!

Lesson 2: Ecosystem Interactions

Activity = ecosystem “game” Ideas = changing resources and populations in an ecosystem

I always chuckle to myself when I think about this lesson. This is clearly how a physicist thinks about ecosystems: create the simplest possible model of an organism and its environment; then little by little add complexity until it begins to behave like a well-functioning ecosystem. This has evolved into a bit of a game that the students learn how to play:

As they get the hang of it, students try more complicated ecosystems with a greater variety of organisms and resources. Soon they begin to see patterns for the characteristics of a sustainable ecosystem. We actually begin the lesson with a quick discussion of this slide.

Students soon learn that their ecosystem games often model ecosystem collapse! The result of their final model shows the importance of biodiversity and how it functions to sustain an ecosystem.

Lesson 3: Biodiversity and Owl Pellets

Activity = owl pellet dissection Ideas = measuring ecosystem biodiversity, human impacts

Here is a map showing a housing development in the town of Ajax. The students play the role of a team of ecologists and mathematicians who have been hired by an environmental organization to study the populations and biodiversity of small mammals in this newly fragmented forest ecosystem. This scenario puts the role of the owl pellet dissection into a realistic scientific context: owl pellets are used by ecologists to monitor populations of small mammals.

I want to emphasize the importance of the scenario as context. The owl pellet dissection is a common activity that teachers choose because it is really cool and gets the kids all excited, which is great. The scientific value of the experience can be magnified when we help students understand why scientists would dissect owl puke. So, after we use the dichotomous key and identify the critters in the pellet, students begin to assemble a statistical model:

This sounds fancy, but we keep the math simple and use the class data from the pellets to estimate the population of each prey species in the forest. This allows our student teams to judge the health of the fragmented forest ecosystem.

Lesson 4: Population Dynamics

Activity = examine simulated population data Ideas = carrying capacity, limiting factors

Inquiry lessons introduce content in small pieces, usually at the moment it is needed. This is when the value of the content can be best appreciated by students: when it helps solve an immediate problem or describes a newfound idea. In this investigation we examine the population of people on Earth and introduce the ideas of carrying capacity and limiting factors. It is very common to think of ecology as something separate from human beings, but we interact with other species and are subject to the same ecological principles as all other life! After a look at people, we examine simulated data with the goal of exploring a disrupted ecosystem. In the example here, I add wolves to the ecosystem 50 days into the simulation.

All this is in preparation for examining real data from an ecological study featured in the next lesson.

Lesson 4b: Ecosystem Disruption

Activity = find interactions through population data Ideas = carrying capacity, limiting factors

The models and toy ecosystems that we introduced in previous lessons are useful for learning the basics, but I want students to work with real scientific data as much as possible in this unit.

The reintroduction of wolves to Yellowstone National Park is a classic example in the study of ecology. It also provides an opportunity to understand how scientists “figure this stuff out”. We often present students with a food web or a model of an ecosystem, but never explain how scientists put together these pictures in the first place. The data in this journal article allows students to do exactly that: put together a model (a food web) of the interactions in an ecosystem. This begins by examining population data and behavioral data for several important species in the park.

The end result, the model, allows us to answer our starting question, which was whether or not the population of wolves could affect the population of trees!

Lesson 5: UN Report on Biodiversity

Activity = read a technical report and produce an infographic

In 2019 the United Nations released a landmark report on biodiversity. When this happened, I knew I wanted my students to read this report. We begin with a video from the Washington Post newspaper:

While most of our students will not become scientists, we can all benefit from being able to better understand and communicate scientific ideas of great social import. This is the rationale behind this lesson.

This is a tough, challenging task. I actually mention this to the students often because I want them to feel gratified when they succeed (they will). We use three class periods and a highly structured investigation to help all our students succeed. The paragraphs from the UN report are of varying lengths and complexity. I distribute the paragraphs amongst my students based on my understanding of their reading level. Students get a lot of support from their group members. I often sit with individual students to help them understand their paragraph and identify the important information. The investigation continues by providing structured thinking processes that helps students design their infographic.

Lesson 6: Biosphere One and Two

Activity = Explore the cycles of matter in Biosphere 2

Ideas = cycles of matter, photosynthesis, cellular respiration

Maybe it's because I was a child of the 80s that I was fascinated by the Biosphere 2 project when it ran at the time: keep 8 people alive in a sealed system for two years. This was an amazing and somewhat crazy ecological (and psychological) experiment. In a TED Talk, one of the biospherians describes the challenges of sustaining this ecosystem and describes the difficulties they had with carbon dioxide levels. This experiment provides an interesting way to introduce cycles of matter and has important connections with carbon dioxide levels in Biosphere 1, the Earth. When I run the science course in the second semester, we do the ecology unit last, which is a sequence I prefer. I can use our understanding of elements and compounds from the chemistry unit and our discussions of sending people into space from the astronomy unit to enhance our discussions in this lesson.

Lesson 7: Biological Processes and Life

Activity = experiment with aquatic plant, experiment with yeast

Ideas = photosynthesis, cellular respiration

This lesson is the experimental heart of the ecology unit. It centres on the key question: “how did people ever figure this out?” and begins with this observation:

What are those bubbles? How could we find out? We begin a sequence of experiments to figure out (or to verify) the biological process responsible for the bubbles. Students do the first experiment involving the plant and baking soda. The others are teacher demonstrations.

Adding baking soda to water

Testing the input chemical

Testing the output chemical

Testing the energy source

Experiments such as these could help people piece together the biological process of photosynthesis. But what about a different, bubbly mystery organism? What is going on here? What is the biological process?

Students know there are two possibilities to explain the bubbles: photosynthesis and cellular respiration. What kind of tests could we perform to find out?

No Organism!

Organism only

Organism and light

Organism and sugar

Any guesses what's going on here?

Lesson 8: Water and Ecosystems

Activity = explore the water cycle Ideas = water cycle, human effects on aquatic ecosystems

In this investigation students explore the water cycle and use their understanding to examine issues around groundwater in Guelph, water conditions in the Grand River (live data is available), and algal blooms in the Great Lakes.

Lesson 9: Analyzing Your Drinking Water

Activity = interpret City of Toronto data Ideas = bioacculumation

The City of Toronto publishes detailed test results for its drinking water. I find this really interesting! Data! https://www.toronto.ca/services-payments/water-environment/tap-water-in-toronto/tap-water-quality-system-reports/

The goal of this lesson is to interpret the data and decide whether any substances are present at an unacceptable level. This provides a bit of scientific background and an important contrast to the water found in the Grassy Narrows First Nation territory.

Lesson 10: Testing Water Quality

Activity = chemical reactions show presence of ions Ideas = testing water quality

This is a lesson based on an activity designed Bianca Radix and Kira Janisse. It uses double displacement reactions to provide a chemical change, which students use as evidence for the presence of ions in simulated water samples. It connects nicely with the City of Toronto water testing data from the previous lesson.

Lesson 11: Carbon and Ecosystems

Activity = examine climate change carbon data Ideas = carbon cycle, climate change

This lesson picks up on the idea of the carbon cycle and helps students explore it in detail. After an introduction, students examine a graphic from the 2013 IPCC report.

The graphic shows historical (pre-industrial) estimates for the movement of carbon and for carbon stores (black numbers). It also shows updated quantities from 2013 (red numbers). This provides a lot of interesting information about the carbon cycle itself and the processes that are intensified by industrial human activity.

Lesson 12: Friendly Fungi!

Activity = read an award-winning science article Ideas = carbon cycle, climate change

Zara Hussan is a 14 year-old student from London, England who was the 2022 winner of the Young Science Writer of the Year award, supported by the BBC.

Her essay describes the relationships between fungi and trees in forests and how that relationship helps to sequester carbon. This is a reading-based activity and is an example of my “active reading” tasks that have been used in a few places in the ecology unit.

The essay is broken up by paragraphs and is placed in a chart with a column for the student’s summary of each paragraph. There are prompts along the way to encourage students to look up vocabulary.

Ecology Homework

I have created homework pages that go along with many of the lessons to help reinforce learning and encourage students to explore real scientific data and social issues. I will give a few examples from the homework:

Homework 8: Water and Ecosystems. This homework activity has students explore the website https://soaer.ca/, which is a massive aquatic ecosystem report for the Mackenzie River Basin. This report is a large-scale collaboration between scientists, indigenous peoples, and local communities. It is a great example of how indigenous knowledge and scientific data can support each other to produce a more complete and meaningful understanding of the environment.

Homework 12: Carbon and Ecosystems Part 2. This homework activity has students exploring a data-mapping resource from the UN Biodiversity Lab. This resource has a lot of great connections to the carbon cycle and climate change, and to their grade 9 geography course. I also include to help students realize that there is a wealth of high-quality scientific information about the environment that is available at their fingertips. I could spend hours on this website, there's so much interesting information!

Wrapping up the tour

I hope you have enjoyed this tour of our grade 9 ecology unit! You are, of course, welcome to use and adapt these lessons and resources for your own class. What makes inquiry work well is a consistent approach to it. If you are interested in trying out some of these lessons, I encourage you to try a block of them or if you are feeling adventurous, try the whole unit! Students will benefit from a consistent approach to their learning and will enjoy the engaging, questioning nature of inquiry-based learning. Finally, let's return to our big questions of inquiry:

(1) How did people ever figure this stuff out?

(2) How do people use this knowledge?

I hope you have noticed how each lesson revolves around these questions and provides students with an authentic look at ecology and our natural world.

Resources

In the resource is below, you can find the Word Handbook document that contains all of the lesson sheets students use. The PowerPoint Course Guide contains all the slides and teacher instructions for each lesson. Please note the PowerPoint does not work properly when opened using Google Slides; You will need to download it and open it in PowerPoint.