Teaching college undergraduates introductory biology includes helping students understand the relationships between genes, mutations, and the environment interacting together as biological evolution. A complete understanding of evolution requires knowledge that spans many biologicalsub-disciplines including genetics, cell biology and ecology. A group of professors at Michigan State University developed case studies for teaching evolution. These cases, known as ‘ Evo-Ed,’ tie the molecular events of mutation and genetic change to proteins and natural selection.
Using a case study example from a National Centers for Coastal Ocean ScienceECOHAB project, edible soft shell clams (Mya arenaria) are susceptible to a potent neurotoxin, called saxitoxin, produced by some dinoflagellates during algal blooms. However, some clams have a genetic mutation that prevents the toxin from killing the clams, which means they’re resistant to poisoning by the toxin, and they can continue to accumulate toxins.Evidence suggests an evolutionary advantage of this mutation. Clams that lack the mutation die from the algal toxins or experience diminished burrowing ability that increases susceptibility to predation.
The Evo-Ed teaching tool includes a short abstract of each case study with links to PowerPoint slides designed to be teaching resources for educators who wish to implement one or more studies into their curriculum.