The Niche Partitioning Interactive can be completed in two 50-minute or one 90-minute class periods.

The concepts of competitive exclusion and niche partitioning are fundamental to the study of ecology and community dynamics. These concepts are addressed in all major biology, ecology and environmental science courses, including pre-AP, AP, IB, and through national and state aligned NGSS standards. The biotechnology application allows for a wide range of implementation strategies.

Key Concepts:

• When two or more species occupy similar niches, competition will lead to exclusion of all but one species.
• Niche partitioning helps explain how species that use the same resource can coexist in the same ecological community without pushing some species to extinction.
• Studying niche partitioning allows scientists to understand how biodiversity is maintained and predict how declining biodiversity could impact the functioning of ecosystems.
• Detailed diet profiles for different species can be determined by analyzing plant DNA.

Module 1 Learning Targets:

• Select which types of data can be used to answer a particular research question.
• Collect and interpret data on animals’ feeding behaviors.
• Support a claim using evidence from ecological principles and authentic field data.
• Explain concepts and models related to species co-existence.
• Identify limitations of traditional forms of data collection.

Module 2 Learning Targets:

• Use DNA sequence data collected from dung samples to identify animal and plant species.
• Identify patterns in data using graphing and statistical methods.
• Support a claim using evidence from ecological principles and authentic DNA sequence data.
• Explain concepts and models related to species co-existence.

Suggestions for Classroom Implementation:

• Show the opening lecture clip to students and make sure they understand the fundamental question they are trying to answer: How do species coexist?
• Ask students: Why do we care? Why is this an important question to answer? Students will be more engaged in the activity if they understand why this research is important. Scientists want to understand how biodiversity is maintained in an ecosystem (in other words, what mechanisms allow multiple species to coexist) and, more importantly, how loss of biodiversity might impact entire ecological communities.
• Students can work through Module 1 at their own pace; depending on your student population, it might be beneficial to regroup after Module 1. It may be helpful to go through the four multiple choice questions at the end of Module 1 together as a class to do a quick check for understanding.
• Module 2 may be more challenging for students. They may need help understanding how to read the Venn Diagram and perform the Sorenson’s Index calculations. You may do these parts of the interactive as a class.
• Throughout the interactive, remind students to summarize their findings and conclusions in the notes and answer the multiple-choice questions.
• The notebook and quiz results are automatically saved in the Progress tab. Students can print their progress or save it to PDF and submit it electronically.
• The accompanying worksheet guides students through the interactive and asks students some additional questions. You may review the worksheet at specific times throughout the interactive to review progress and check for understanding.

The data that students collect and analyze comes from a study conducted by Dr. Robert Pringle’s lab at Princeton University. (Tyler R. Kartzinel, Patricia A. Chen, Tyler C. Coverdale, David L. Erickson, W. John Kress, Maria L. Kuzmina, Daniel I. Rubenstein, Wei Wang, and Robert M. Pringle. DNA metabarcoding illuminates dietary niche partitioning by African large herbivores. Proceedings of the National Academy of Sciences.112: 8019-8024, 2015.)

This spreadsheet of the data used in this interactive includes the barcode sequence and plant classification as grass or browse for each plant species. Plant species present in a sample are marked as 1, and species absent are marked as 0.