Listen, do you smell something? Signal detection theory in Biology

How do organisms detect changes in their environment, and how do scientists and their instruments detect changes in experimental conditions, such as: How does a photoreceptor detect the presence of a photon? How does a doctor detect the presence of a tumor? How does a cell detect the presence of a chemical, such as a morphogen, a chemoattractant, or a nutrient?


In this module, the students become the detectors, each making decisions about whether they heard a change in sound, so it is suitable for a large class. Students learn how to compute the d’ of stimulus discriminability, how to understand d’ graphically, learn the tradeoffs of sensitivity and specificity, and apply these to problems in cell and organismal biology. Student learning is assessed through a pre-class quiz, an in-class assignment, and an exam question.


Little Niche on the Prairie

The series of prairie modules enables students to examine fire disturbance and its known effects on prairie plant populations (Week 1), collect your own field data on restored prairie parcels with different season-of-burn treatments (Week 2), analyze that data (Week 3), and explore the implications and constraints of burning and other management techniques for prairie restoration and management (Week 4). Thus, each week builds on the activities from the week before and essentially addresses a different component of a scientific paper – the Introduction (Week 1), Materials & Methods (Week 2), Results (Week 3), and Discussion (Week 4).

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