This case study in the form of a set of PowerPoint slides examines the evolution of toxin resistance in clams.
one to two class periods
This case study is also appropriate for zoology and ecology classes. The toxin resistance is quite interesting and should be engaging to a qualified student; however, background in cell membrane physiology should be a prerequisite.
Correspondence to the Next Generation Science Standards is indicated in parentheses after each relevant concept. See our conceptual framework for details.
- There is a fit between organisms and their environments, though not always a perfect fit.
- An organism’s features reflect its evolutionary history.
- Some traits of organisms are not adaptive.
- There is a fit between the form of a trait and its function, though not always a perfect fit.
- New heritable traits can result from mutations.
- Mutation is a random process.
- Organisms cannot intentionally produce adaptive mutations in response to environmental influences.
- Complex structures may be produced incrementally by the accumulation of smaller advantageous mutations.