Sara is very active in volleyball, basketball, and softball. She is a member of her school's student council and enjoys reading almost any type of literature. Because Sara is "very interested in protecting the environment," she is interested in a career in environmental protection or law. Sara's seventh grade science teacher "had a huge impact on my pursuit of science."
Last year, Sara's project showed that strong caffeine solutions killed garden pests. This year, she wanted to see if a lower concentration of caffeine could inhibit reproduction of slugs without killing the beneficial red and black worms.
Sara prepared caffeine solutions ranging from 0.0001% to 1.0%. She placed soil soaked with the caffeine solutions in plastic containers with red worms and spotted garden slugs. For the smaller black worms, Sara used micro test tubes instead. She checked the worms and slugs every day, counting survivors. After 30 days, she counted the number of eggs, cocoons, and young worms and slugs in each container or test tube. Slugs could not reproduce in solutions stronger than 0.005% caffeine, but at this concentration, red worms and black worms reproduced more frequently than control animals.
