their own is to use formulas in the spreadsheet to calculate the
allele frequency and gamete pool repopulation.
Our two-part lesson is an engaging alternative to static, equation-based discussions that have students “plug-and-chug” their way
through HWE. Students actively participated throughout both parts
1 and 2 across all classes. Although the instructions for part 2 can
be complicated because each group is carrying out their own simulation with their own event cards, in the end students observed that
each group changes in different ways because of different events (drift,
natural selection, or both). Using authentic research data to validate
simulation results provided a meaningful and impactful experience
through real-world application of a biological mathematical model
carried out through simulations.
Some existing HW activities and problem sets emphasize “
working the math weakness” out of students by presenting allele and
genotype frequency calculations lacking biological context, but that
approach leaves students with the perception that the goal is to plug
numbers into an equation rather than applying a model to a biological phenomenon. Smith and Baldwin (2015) evaluated several HW
problems, and although some were problem sets with actual allele
frequencies, many activities fell short of providing context or linking
microevolution to existing problems that are broadly accessible to
students. In contrast, our clam activity gives students simulated populations and natural-selection-type and drift-type events whereby
students can experience the resulting changes to allele frequency in
the context of actual biological examples. Broadcast spawners like
clams facilitate understanding of a gamete pool more readily than
organisms with internal reproduction, such as humans. Here students have the opportunity to see fusing gametes (using a video)
and then apply the principles of HWE. The context of resistant
and sensitive alleles in the clam populations provides real-world
examples to observe and manipulate, combined with the ability to
relate simulated results to authentic research data.
This collaboration began as a working group at the 2017 BioQUEST
Curriculum Consortium meeting at Michigan State University. We
are grateful to Kristin Jenkins and the BioQUEST/QUBES staff for
their role in facilitating this project. We also thank Merle Heidemann,
who played a key role, both in the development of the original Evo-Ed
Clam Case and in the clam activity working group. Partial support
for this work was provided by the National Science Foundation’s
DRK12 program (award no. DRL-1620746). Any opinions, findings,
and conclusions or recommendations expressed in this material are
those of the authors and do not necessarily reflect the views of the
National Science Foundation.
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KAITLIN BONNER is an Assistant Professor of Biology at St. John Fisher
College, Rochester, NY 14618; email: firstname.lastname@example.org. DENISE PIECHNIK
is an Assistant Professor in the Biology and Health Sciences Division at
University of Pittsburgh–Bradford, Bradford, PA 16701; email:
email@example.com. JENNIFER KOVACS is an Associate Professor of Biology
at Spelman College, Atlanta, GA 30314; email: firstname.lastname@example.org. ALEXA
WARWICK is a postdoctoral scholar in Evolution Education and Outreach
at the Beacon Center at Michigan State University, East Lansing, MI 48824;
email: email@example.com. PETER WHITE is an Assistant Professor in the
Lyman Briggs College and the Department of Entomology at Michigan State
University, East Lansing, MI 48825; email: firstname.lastname@example.org.