Case Study – Evolution and White Striped Clovers


This case study was designed for students in Advance Placement biology.  It requires students to look at two phenotypes of clover (polymorphisms) and compare the types of clover found in different areas.  In addition to analyzing data, students determine how the production of cyanide by clovers with a white stripe is an evolutionary advantage is some environments, but not others.

Students are exposed to the idea of fitness and to relative fitness and return to Kettlewell’s experiment on the evolution of moths in dark and light forests.

Finally, students are asked to apply their understanding of fitness to elephant populations in Africa.

Grade Level:  11-12  | Time Required:  2 – 3 hours


HS-LS4-3 – Apply concepts of statistics and probability to support explanations that organisms with an advantageous heritable trait tend to increase in proportion to organisms lacking this trait.
HS-LS4-4 – Construct an explanation based on evidence for how natural selection leads to adaptation of populations.