JoinAll Case Studies
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In keyword search, list the criteria you would like to find cases. Multiple criteria can be listed separated by commas (i.e. directed, high school)
Educational levels are defined as follows: Elementary, Middle, High School, College
Types of cases are defined as follows: Analysis/Issues, Clicker, Debate, Intimate Debate, Demonstration, Dilemma/Decision, Directed, Discussion, Interrupted, Jig-saw, Journal Article, Laboratory, Student Presentations, Mini-case, Problem-Based Learning, Public Hearing, Role-Play, Trial, Flipped, Game
By Alison J. Albee, J. Megan Woltz, Taylor Kemp, Emma Mays, Tylor M. Miller, Eric Fisher, Amanda Loutzenhiser
This case study focuses on the characteristic of tusklessness in the African elephant population of Gorongosa National Park, Mozambique, to examine molecular and macroscopic aspects of evolution. Students are introduced to the plight of African eleph...
Those Who Wish to Sing Always Find a Song
By Justin W. Merry
This interrupted case study examines the evolution of cricket stridulation in the Hawaiian Islands, where a silent, non-stridulating phenotype of Teleogryllus oceanicus has evolved and spread throughout Hawaiian populations in just over a decade in r...
Is It Hot in Here, or Is It Just Me?
By Amanda J. Chunco, Patricia A. Thomas-Laemont
Menopause is an evolutionary conundrum. Why would something evolve that reduces the number of potential offspring that an individual can have? And yet, even though rare, menopause not only exists, but has evolved multiple times in a few different spe...
By Kristen H. Short
This interrupted case study leads students through an exploration of the evolutionary origin of apparently cooperative guarding behavior in meerkats. Students generate hypotheses, evaluate the predictions associated with them, and then analyze graphi...
Are Oxpeckers Friends or Foes?
By Andrea M.-K. Bierema
Symbiotic relationships are interactions between species that live closely with each other and are commonly separated into three types: parasitism, mutualism, and commensalism. Students are often under the impression that these types are distinct and...
Directed Evolution of Nanobodies for COVID-19 Prevention
By Stefanie H. Chen, Andrea Bixler
Directed evolution is a laboratory process that mimics the steps of natural selection to efficiently determine variants of proteins or organisms that respond more effectively to a selected condition. This process was recognized by the 2018 Nobel Priz...
By Kelsie J. Anson, Briana N. Van Treeck, Jake J. Flood
Cellular metabolism is traditionally taught in undergraduate biochemistry courses through the memorization of complex biochemical pathways. As such, many students find it difficult to relate the subject to current research in biology and in medicine....
The Grass is Greener in Kentucky
By Thomas S. Nühse
Kentucky 31 is a widely grown variety of tall fescue grass that owes its extreme stress resistance, but also its toxicity, to an endophytic fungus. It is difficult to decide where to place this symbiosis along the mutualism-parasitism spectrum. In th...
The Shifty Salmon of Auke Creek
By David A. Tallmon
Pacific salmon are culturally, ecologically, and economically important throughout their geographic range. They are also increasingly depleted and threatened with extinction. This interrupted case study in three parts focuses on issues surrounding mi...
By Stefanie H. Chen, Carlos C. Goller, Melissa C. Srougi
In this directed case study, students assume the role of investigators for the Centers for Disease Control and Prevention (CDC) as they examine and compare different DNA sequences from human patients infected with SARS-CoV-2, the coronavirus that cau...
By Laura Pickell
This analysis case study uses a jigsaw activity in which students learn about characteristics of the novel coronavirus causing COVID-19, SARS-CoV-2. The protagonist of the case, “Malik,” is a public health nurse who has been assigned to answer ph...
By Kathleen A. Nolan
This case study examines the population dynamics of the horseshoe crab, which is sometimes described as a “living fossil.” Students are shown PowerPoint slides that are interspersed with clicker questions about the biology, life history strategie...
By Susan A. Weiner
This case study in comparative physiology explores the connections between physiology, evolution and behavior. Students assume the role of researchers who have discovered the body of a rare and poorly studied (fictional) monkey, Callicebus imagini. S...
By Parks Collins, Jason Macrander
This interrupted case study tells the true story of Karl P. Schmidt, a herpetologist and museum curator who was bitten by a venomous snake in 1957. Like a true scientist, Schmidt recorded notes about his symptoms until the very end when he died. Stud...
Peppered Moths and the Industrial Revolution
By Avril M. Harder, Janna R. Willoughby, Jaqueline M. Doyle
This interrupted case study was written for students to gain a better understanding of evolutionary concepts and principles as they develop their skills in hypothesis creation, experimental design, and critical analysis of experimental assumptions. T...
By Janna R. Willoughby, Avril M. Harder, Jaqueline M. Doyle
This interrupted case study is based on a journal article that describes the rapid adaptation of a population (in this case, steelhead trout) in response to a shift in environmental conditions despite genome‐wide reductions in genetic diversity. Fi...
Evolution by Natural Selection in Oldfield Mice
By Katherine S. LaCommare, Peter A. Van Zandt
The theory of evolution by natural selection is simple, elegant, and profound. Yet, a large number of undergraduate students including biology majors, medical students, and pre-service science teachers maintain a large set of misconceptions that inte...
Speciation and the Threespine Stickleback
By Joan Sharp, Erin Barley, Kevin K.-W. Lam, Suraaj Aulakh, Allison Cornell, Kathleen A. Fitzpatrick
This case study teaches students about allopatric speciation through an investigation of the benthic and limnetic sticklebacks of Paxton Lake, which are among the youngest species on Earth, diverging from each other after the Pleistocene glaciers mel...
The Cold Never Bothered Me Anyway
By Nora S. Green
Woolly mammoths and other cold-adapted animals, such as reindeer and musk ox, developed a number of adaptations that allowed them to survive in frigid environments. These include small ears, thick fur, and even long tusks. Many of these species devel...
By Annie Prud’homme-Genereux
This flipped case study examines the selective pressures that have affected the evolution of diverse human skin pigmentations. To prepare for the case, students begin by watching videos and doing research on their own. In class, students use the info...
By Brett C. Couch
Why are chilies so hot? This case study begins with a story about an undergraduate student who is inspired to learn about capsaicin production in chilies after losing a spicy chicken wing eating contest. The case was developed as an initial activity ...
By Amber J. Raven, Jessica Williamson, Raelynn D. Haynes
This case study was developed for an upper-level undergraduate evolution course in order to provide an example of natural selection in hominids and encourage critical thinking and understanding of the subject. The case focuses on the cognitive evolut...
Selection on a Case by Case Basis
By Adam R. Irvine, Eva S. Horna-Lowell, Mathew J. Driscoll, Emily D. Broder
This "clicker case" gives students an opportunity to apply their understanding of three different types of selection (directional, stabilizing, and disruptive) to a variety of model systems. The case describes each type of selection in detail, presen...
By Maria P. Chadiarakou, Anitha Sundararajan, Ingrid E. Lindquist, Gabriella A. DeFrancesco, Madeline Kwicklis, Drew A. Lighthall, Natasha E. Farmer, Michèle I. Shuster, Joann Mudge
DNA sequencing and analysis (bioinformatics) is an increasingly important tool for understanding biological data, including medical data. In this case study, students will be exposed to DNA sequencing to quickly identify how an outbreak of methicilli...
Life Tables, Darwin’s Finches, and the Dynamics of Small Island Populations
By Whitley R. Lehto, Shannon M. Murphy, Mayra C. Vidal, Robin M. Tinghitella
This case study uses Darwin’s finches to teach students about life tables. Life tables are tables of statistics that relate to life expectancy and reproductive output for a population of organisms. Students are asked to tabulate traditional life ta...
Animals Can Run Away, but Plants Must Stay
By Nicole D. Tunbridge, Carol Pollock, Joan Sharp
In this PowerPoint-driven case study, students consider the many challenges faced by plants and discuss which of these might induce a morphological response. Examples of phenotypic variation within a plant species are presented and students discuss i...
By Clyde Freeman Herreid
This interrupted case study for the flipped classroom examines the interaction of plants and their mycorrhizal partners. The latter is one of the most widespread and vital symbiotic relationships in the world and can be seen in the videos that studen...
No Matter If You’re Black or White
By Srikripa Chandrasekaran, Linda Niedziela
Human populations have adapted to varying intensities of sunlight with varying tones of skin coloration. The balanced interplay between melanin content and UV absorption allowed populations to successfully migrate from sub-Saharan Africa by influenci...
Testing for Grazer Adaptation to Toxic Algae
By Michael B. Finiguerra, Hans G. Dam, David E. Avery
The intent of this interrupted case study is to present a clear example of both the scientific method and evolutionary adaptation in a model system consisting of marine grazers (copepods) and toxic prey (phytoplankton). Briefly, a certain toxic phyto...
The Evolving Genetics of Disease Resistance
By Jennifer M. Dechaine
This interrupted case study for the flipped classroom applies evolutionary genetics research to human health. Students learn about a naturally occurring, but rare, allele of the CCR5 gene, CCR5-Δ32, which provides resistance to HIV. They use data fr...
By Jasmine D. Edgren, Erica F. Kosal
This case study was written for an introductory course for biology majors who are first learning about embryonic development. The case is composed of several parts and involves a storyline about a team of researchers who find frogs and eggs in bamboo...
By Rebecca L. Hite
This case study introduces students to the "Red Queen Hypothesis." The hypothesis states that when two species compete for a limited resource or exist in a predator-prey relationship, in order for the antagonists to remain in relative population equi...
By Mayra C. Vidal, Kylee Grenis, Whitley R. Lehto, Robin M. Tinghitella, Shannon M. Murphy
This case study uses an interactive activity to illustrate density dependence in ecology classes. We developed a "hunt" using paper butterflies with warning signals on the upper side of the wings and symbols that indicate if a butterfly is noxious un...
By Fiona E. Rawle, Marc Dryer, Joan Sharp
In this clicker case study for a flipped classroom, students familiar with the stages of meiosis work in small groups to determine the predicted genetic makeup of the parthenogenetic offspring of a Komodo dragon, based on four different types of part...
By Celeste A. Leander, Pamela Kalas
This case study focuses on the intersection of defining a scientific species and defining a legal species. The compelling story of Lolita, an orca whale in captivity, is used to highlight the legal significance of species declaration. Students will w...
Bioluminescence and 16th-century Caravaggism
By Yunqiu (Daniel) Wang
This case study looks at the probable connection between bioluminescence and Caravaggio's painting style in the 16th century in order to explore the mechanism of bioluminescence and its role in animal evolution and modern medicine. Recent studies hav...
Giant Pandas, Hormones, and the Evolution of a Lazy Bear
By Patricia J. Moore
This clicker case study looks at the role of hormone cascades in homeostatic control of metabolism in a charismatic organism, the Giant Panda. The case explores how Giant Pandas have adapted to a nutritionally poor food resource, bamboo, throug...
By Conrad Toepfer
A common misconception is that Darwin suggested that something as complex as the eye could not have evolved through natural selection. While the misunderstanding often comes from an incomplete reading of his argument, we have long known that intermed...
By Gary H. Laverty
The Aedes aegypti mosquito is the major vector for transmission of numerous viral diseases, including yellow fever, dengue, and now, Zika. Interestingly, different subspecies of A. aegypti are known to exist in close proximity but with considerable g...
Why Did the Snake Cross the Road?
By Milton T. Drott, Mark A. Sarvary
Although Hardy-Weinberg equilibrium is a fundamental part of introductory biology classes, students often have difficulty understanding its implications. This interrupted case study places students in the role of small teams who are conducting prelim...