In this lab, students measure the amount of variation in a natural population of terrestrial wood lice and then determine which traits are subject to selection by predators by performing a simulated predation experiment.
By examining variation in a natural population of real organisms and subjecting them to artificial predation, students are able to explore the relationship between variation and selection. The availability of wood lice and the simplicity of the materials make this exercise especially attractive.
Though this can be a 3 hour lab period, you could also spread it out into two labs, with the first lab a visit to a natural area so that students could collect their own specimens.
Variations on the experiment can be taught at the high school level (AP Biology).
Correspondence to the Next Generation Science Standards is indicated in parentheses after each relevant concept. See our conceptual framework for details.
- An organism’s features reflect its evolutionary history.
- Artificial selection provides a model for natural selection.
- Inherited characteristics affect the likelihood of an organism's survival and reproduction. (LS4.B, LS4.C)
- Natural selection acts on the variation that exists in a population. (LS4.B, LS4.C)
- Natural selection acts on phenotype as an expression of genotype.
- A hallmark of science is exposing ideas to testing. (P3, P4, P6, P7)
- There is variation within a population. (LS3.B)