Lesson 3.3: Calculating a Biodiversity Index and Presenting the Data

Lesson Objectives

Students will:

• Analyze their biodiversity inventory data to identify trends, patterns, and comparisons with ecological school grounds.

• Use this data analysis, as well as observations and discussions within their groups, to develop a story about the quality of biodiversity on their school grounds.

• Calculate the biodiversity index of their school grounds using the data they collected in Lesson 3.2.

• Represent their observations using words, drawings, labels, and maps.

• Work in groups to accomplish these tasks.

• Document their thoughts and insights about the activities in this lesson in a journal.

Assessment Opportunities

• Contributions to class discussion

• Quality of teamwork while working on the school grounds

• Accuracy of biodiversity index calculations

• Data visualizations

• Claim-Evidence-Reasoning posters

• Descriptions of observations in student journals

• Journal entries describing key takeaways from this lesson

• Preparation of slide(s) for presentation in Lesson 5

Background

A biodiversity index gives scientists a consistent measure by which to talk about and compare the biodiversity of different areas. It is a scale of the diversity of plant and animal species at your study site. In general, scientists often discuss the diversity of genes, species, and ecosystems in an area. Genetic diversity defines the number of different genes within a species in an area. Species diversity measures the number of species in an area. Ecosystem diversity describes the number of kinds of ecosystems in an area. There is some debate as to the most accurate measure of calculating biodiversity, with the Simpson and Shannon indices most widely accepted.

In this lesson, students will use a simplified biodiversity index model that will let them see how scientists use math to calculate the species diversity of their school grounds. Through this exercise, they will discover that the closer the diversity index is to 1, the more likely that their habitat is healthy and diverse. If teachers prefer to use the Simpson or Shannon Index, there are many online resources that provide instruction.

The terms "school grounds" and "schoolyards" are used interchangeably in this lesson.

Getting Ready to Teach

This lesson follows a sequential step pattern and requires background knowledge (see above). It is recommended that teachers read through Section 4, Calculating a Biodiversity Index , on page 9 of the Schoolyard Biodiversity Investigation Educator Guide for a more in-depth explanation of this lesson. Teachers should at least refer to the Sample Wildlife Biodiversity Index Data Collection Document before beginning the lesson. Students will be putting their data into a presentation form (charts, graphs, etc.) to tell a story about the level of biodiversity they observed on the school grounds and how it compares to the elements of ecological school grounds they discovered earlier.

Students should be prepared to spend time outdoors on their school grounds for part of this lesson. They should have working knowledge of the terms "species diversity," "biodiversity index," and "random sampling" prior to beginning this lesson.

Please open the links prior to teaching the lesson. You may also refer to additional resources at the bottom of this page.

The Lesson

Part I. Review the School Grounds Biodiversity Inventory Data

1. Students should have copies of the schoolyard biodiversity inventory data they collected in Lesson 3.2.

2. Review the data and look at the difference between the vegetation and wildlife data tables. The Vegetation Survey already has specific numerical data that can be used for calculation of the Diversity Index. The Wildlife Survey is more general. To calculate a Diversity Index for wildlife, more specific data must be collected.

3. Give student groups a copy of the Wildlife Biodiversity Index Data Collection Document. When collecting wildlife data this time, students will:

a. Be more specific in the data they collect.

b. Count and tally only the animals they find or observe On Site (in their study area).

c. Tallies will be taken for the total number of different species, total number of each species, and total number of all species found or observed for each group of animals.

d. After finishing the observation, the diversity index will be calculated back in the classroom.

Part II. Biodiversity Inventory: Wildlife Survey #2

4. Back at their study areas on the school grounds, student groups should complete their diversity data collection using the form they were given. They may make additional observations (words, drawings, photos, etc.) in their journals.

Part III. Calculate the Simplified Diversity Indices

5. Back in the classroom, use this equation to calculate the Simplified Diversity Index (SDI) for each species category and for the total species in the habitat:

Simplified Diversity Index = TOTAL Number of DIFFERENT SPECIES

TOTAL Number of ALL PLANTS or ANIMALS FOUND

Part IV. Analyze the Simplified Diversity Indices

6. The SDI measures how diverse each plant or animal group is in the schoolyard.

7. Let's analyze what the SDI means in more detail. The closer the number is to 1, generally the more diverse the group. However, a lower SDI value may be because there is a large number of the same species (a high species evenness). A higher SDI value could be because there are many different species, with a low number of each of the species present (a high species richness).

8. To figure out Species Richness, have each group count the number of DIFFERENT SPECIES (specify plants or animals) in their study area. (Students should refer to their Wildlife Biodiversity Index Data Collection Document, column 2.) Compare the results for each study area. The areas with the highest numbers are most rich in species. They may be more ecologically complex than the study areas with lower numbers of species.

9. To figure out Species Evenness, have each group count the number of EACH SPECIES (specify plants or animals) in their study area. (Students should refer to their Wildlife Biodiversity Index Data Collection Document, column 3). Compare the results. The closer in numbers of each species in a study area, the more diverse the ecosystem.

10. Animals seek to live in habitats that provide adequate food and shelter, including the type and variety of plants in a suitable arrangement. Ask students to consider this question and discuss it: "Is there a correlation between plant diversity on the school grounds and animal diversity?"

11. Here are some additional discussion questions:

a. "Are there areas of the school grounds that have a higher SDI than others? Why?"

b. "If we collected this data at a different time of year, would the SDI calculations be the same? Why or Why not?"

c. "What are some limitations or problems with random sampling to calculate diversity?"

12. Students should note their conclusions in their journals.

Part V. Present the SDI Data

13. Today we are bombarded with data. Sometimes it is presented in ways that are effective in explaining how it impacts our lives, other times not.

14. Using data effectively is essential to make a case for something you believe in. Most decisionmakers rely on data to justify decisions that involve funding or altering "business as usual" practices, such as the way school grounds are used and managed.

15. Using charts or graphs (or other ideas for presenting data visually), students should take the data they have calculated and present it in a way that tells a story about what it represents. What should happen to improve the school grounds for biodiversity could also be part of this story.

16. This question could be a guide: "What is the state of biodiversity on our school grounds, and why and how could it be improved?"

Part VI. Compare Conclusions to Ecological School Grounds

17. Refer back to the elements of ecological school grounds students researched in Lesson 2.3.

18. Compare the results of the plant and animal biodiversity surveys, SDIs, and observations made during the surveys to those elements on a Claim-Evidence-Reasoning (C-E-R) poster. Include the data visualization story.

19. Hang the posters and have everyone view them. Then discuss as a class your conclusion about how biodiverse and ecological your school grounds are, and what could be done to improve them. Record these conclusions in your journals.

Part VII. Presentation Preparation

20. Have students open their journals and record their main takeaways from this lesson, including big ideas, relationships, and goals.

21. Remind them that this overall project culminates in a presentation or other means of advocating for more ecological and culturally diverse school grounds.

22. Using the Presentation Rubric, ask students to record some ideas in the "Presentation Ideas" section of their journal for the slide(s) or piece(s) of information to be included from Lesson 3 in the project presentation, if you will not be using slides. Label these ideas "Lesson 3.3" or with some other label that helps organize the information to align with the rubric. Students can work in their groups or individually.

23. Include the data visualizations in the "Presentation Ideas" for this lesson.

24. Collect the journals to keep for assessment and to ensure that all students are collecting the information needed for their presentations.

Additional Resources

• 4 Different Ways to Measure Biodiversity infographic

• Abundance, Species Richness, and Diversity video

• Telling Stories with Data in 3 Steps (Quick Study) video

• Five Data Storytelling Tips to Improve Your Charts and Graphs video

Extensions

• Students can also use this electronic data sheet (Google form) to record the different species of plants and wildlife they observe as part of their biodiversity inventory.

• Survey another area, either on or off the school campus, or survey the same areas at another time and compare the SDIs between the two sampling incidents as a comparative field investigation.

• Explore the website Our World in Data to discover data sets that are relevant to biodiversity or cultural connections with nature. NatureServe is another source for maps and data sets. Data sets are free and downloadable.

• Use a free data tool such as Datawrapper or Tableau Public to make a compelling data visualization that explains why you believe your school grounds should be managed more for biocultural diversity. Use the SDI data you collected as part of your data visualization.

In the Next Lesson (L 4.1)

Students will use the data and information they have collected and researched thus far to envision their ecological, bioculturally diverse school grounds and make a plan for implementing their vision.

Acknowledgments

• This lesson is adapted from the Association of Fish and Wildlife Agencies, Schoolyard Biodiversity Investigation Educator Guide, 2011