Interactions are at the core of many ecological and evolutionary forces in nature.
Plant–soil interactions provide a rich example of the interconnectedness of living
systems, but they are hidden from everyday view and overshadowed in the
classroom by more popular teaching examples involving animals, reptiles, or
invertebrates. To highlight the importance and relevance of plant–soil relationships,
we devised a simple role-playing activity suitable for college students. Specifically,
the activity simulates how feedbacks between plants and soil environments influence
plant species abundance and community richness. With this activity, students will
gain a better understanding of these prolific, but overlooked, forms of biological
interactions that impact the diversity and functioning of ecosystems.
Key Words: Diversity; feedbacks; fungi; interactions; plants; soils.
Biological interactions are a predominant way in which students learn
about the ecological and evolutionary processes that influence biodiversity. However, most general biology textbooks primarily use animals,
reptiles, or invertebrates as case studies to demonstrate the importance
of interactions in nature (Uno, 1994; Link-Perez et al., 2010; Schussler
et al., 2010). This contrasts with the facts that (1) plants are ubiquitous,
and students encounter them regularly in their daily lives; and (2) most
interactions that plants rely on happen belowground. Since it can be
difficult to present plants and (especially) soils in exciting ways, many
students unintentionally cultivate a fauna-centric view of the natural
world (Wandersee & Schussler, 2001). To highlight the importance
and relevance of plant–soil relationships, we devised a simple role-playing activity suitable for college students.
Research on plant–soil interactions and their importance in ecology
and evolution has blossomed in recent decades. Specifically, feedbacks
occur when plants condition soil properties and, in return, are affected
by the conditioned soils (Bever, 1994). Negative feedbacks reduce the
performance of individuals of the same species in relation to other spe-
cies, resulting in negative frequency-dependent selection (Packer &
Clay, 2000; Mangan et al., 2010). Positive feedbacks encourage con-
specifics to thrive in their respective soils more than heterospecifics,
leading to the monodominance of single species (e.g., invasive species).
These reciprocal interactions can shape the nonrandom assembly of
plant communities (Bever, 1994; van der Putten, 2013).
The activity has two main purposes: (1) to engage students in a more
active interpretation and discussion of the interactions between plants
and soils, and (2) to connect these interactions to larger concepts of
drivers of biodiversity and ecosystem function. This aligns with a core
concept in biology (sensu AAAS, 2011): Living systems are intercon-nected and interacting. Plant–soil interactions provide a rich example
of the interconnectedness of living systems, but they are hidden from
everyday view and overshadowed by more popular teaching examples. By actively role-playing plants and soils, students can see how
these interactions operate in nature.
The primary learning objective of this activity is for students to recognize how plant–soil interactions alter patterns of plant community diversity. This activity simulates how plant–soil feedbacks influence
species abundance and richness over time. It is recommended that
the game first be played in Negative Mode. A Positive Mode variation
is introduced at the end of this description.
Negative Mode demonstrates how negative plant–soil feedbacks
promote and maintain diversity. When the same plant species and soil
properties are matched, the plant dies. Oppositely, plants survive
when species and conditioned soils are mismatched. For example,
The American Biology Teacher, Vol. 81, No. 4, pp. 287–290, ISSN 0002-7685, electronic ISSN 1938-4211. © 2019 National Association of Biology Teachers. All rights
reserved. Please direct all requests for permission to photocopy or reproduce article content through the University of California Press’s Reprints and Permissions web page,
www.ucpress.edu/journals.php?p=reprints. DOI: https://doi.org/10.1525/abt.2019.81.4.287.
THE AMERICAN BIOLOGY TEACHER BRINGING PLANTS & SOILS TO LIFE THROUGH A SIMPLE ROLE-PLAYING ACTIVITY
TIPS, TRICKS &
Bringing Plants & Soils to Life
through a Simple Role-Playing
• MICHAEL E. VAN NULAND, MIRANDA
CHEN, BENJAMIN J. ENGLAND