Students will investigate the food preferences of garden slugs (Arion subfuscus) using simple equipment including margarine tubs, graph paper, scissors, and common plants, both wild and cultivated. The exercise is genuine scientific research in that: a) the student devises his/her own “research question” about slug feeding behavior, and b) the results are truly unknown to the student-experimenter (and possibly to the instructor) prior to the experiment. In carrying out the complete set of experiments described below, students learn that one way to achieve precision and accuracy is by designing experiments with many replicates.
The following laboratory write-ups are included:
I. Slugs and the Scientific Method: This exercise uses slugs to teach the difference between “observation” and “opinion” and introduces the concepts of “controls” and “hypothesis testing.”
II. The Vermiculturist’s Experiment: This paper exercise illustrates the importance of controls, variables, and replicates in experimental design.
III. Food Preferences of Slugs: Students design and carry out their own experiment to test a slug’s preference between two or more food sources.
IV. Food Preferences of Slugs (continued): Students will also benefit from the opportunity to further practice their experimental design skills by looking more closely at the complex question of “How do you determine what a slug really likes?” This lab should be undertaken at a time of the year when slugs can be collected easily.
Note: There is a Middle School and a High School version of this lab. Files are labeled as such.