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Aside from consultations on organisms, we also offer advice on the proper care and maintenance of the specimens, measures that are often overlooked. It is important to allot adequate time for research into the care of an organism, selection and acquisition of the specimen, creation of its habitat, and daily maintenance needs. The list below contains information on some of our most popular organisms for science fair projects. Daphnia Known for their jerking movement through water, Daphnia are ideal specimens for physiological exercises and toxicity tests. The organisms are filter feeders that exhibit behavior in the laboratory setting very similar to their natural behavior. Though they are known as “water fleas,” Daphnia are not related to the terrestrial flea. These organisms require special care. It is best to use Daphnia cultures in experiments within 24 hours of receiving them. We suggest introducing the organisms to the new environment by gently submerging the opened shipping jar in their habitat, not dumping the organisms from the shipping container. Submerging the jar prevents air bubbles from collecting under the organisms’ shells, which would lift them to the surface and decrease their chances of survival. Daphnia are sensitive to the chemistry of the water in their habitat, so make sure the water source is either springwater or filtered pond water. We strongly advise against the use of tap water as it may contain chlorine levels that are lethal. Also avoid distilled water, which does not have the essential minerals required for osmotic equilibrium. Environment plays a critical role in development. The organisms are most successful when raised at room temperature and kept out of direct sunlight. Daphnia reproduce asexually and sexually, but under ideal environmental conditions most populations will consist of only females. When conditions become too stressful (e.g., food shortage, poor water quality, extremes in temperature, and overcrowding), males will be produced and sexual reproduction will begin to take place. Recommended products Planarians Among the simplest types of multicellular organisms, planarians are an excellent choice for regeneration studies. The black and brown varieties (Dugesia dactyligeria and Dugesia tigrina) are the best options because they do not take as long as the white planarians (Dugesia morgani) to regenerate. The flatworms can be kept in an 8” culture dish or a shallow, soap-free container that holds about ¾ to 2” of springwater. Transfer the specimens to a fresh dish of springwater each day. We do not recommend tap water because it contains metal ions and chlorine, which are deadly to planarians. These self-healing organisms are highly sensitive to intense light, temperature, and pH; therefore, it is important to not make any drastic changes to these environmental factors once you begin experimentation. When you receive your planarians, do not feed them for the first week. After that period, feed them foods such as fresh beef liver, hard-boiled egg yolk, Lumbriculus, and pieces of earthworm. Recommended products
Lumbriculus variegatus, a common freshwater annelid, is an excellent alternative to a planarian for regeneration studies and water quality projects. The blackworms are hardy and easy to raise either at home or in the classroom. Create a home for your worms by filling a pan or aquarium with 2 to 3” of springwater (or aged and dechlorinated tap water) at room temperature and lining it with brown paper towels. Sinking fish food is the worms’ food of choice, but they can survive bouts of irregular feeding or long periods of starvation. In the laboratory, populations can double in about 3 to 4 weeks. Recommended products Fruit flies Students with an understanding of genetics and an eye for detail will find that Drosophila melanogaster, the common fruit fly, offers challenging and interesting project ideas. Subjects can be as simple as the fruit fly life cycle or as complex as sex-linked inheritance of traits. The laboratory-raised cultures are easy to use and require few supplies for handling and rearing. Results can be obtained in a reasonable amount of time. Within a week of receiving your culture, you can expect to see the F1 generation emerge. After crossing the F1 generation, the F2 generation should appear within 2 weeks. You will have your choice of several phenotypes, including wing structure, eye pigmentation, and body coloration. We have even developed flightless strains, so parents and teachers need not fear they will be overrun with black clouds of fruit flies. The right materials can make your work less complicated. For instance, FlyNap® prepares flies more safely than ever before. It anesthetizes young flies for up to 50 minutes, making handling for evaluation of expressed phenotype easier. Supplies can be purchased separately and in bulk. With 6 weeks of advance notice our Drosophila Lab can also create customized F1 crosses for your project needs. Recommended products Terrestrial isopods Commonly mistaken for insects, these relatives of lobsters and crayfish are perfect for behavioral investigations. The isopods most often used for classroom studies are Armadillidium vulgare (pill bug or roly-poly) and Porcellio laevis (sow bug). Isopods can live in almost any plastic container, provided there is a layer of moist soil covered with dead leaves, twigs, mulch, or bark. A chunk of raw potato or apple can serve double duty by providing both food and moisture. The habitat must be kept moist at all times—but not soaking wet—because the specimens obtain the oxygen they need through gill-like structures found on the bottom of their legs. These organisms are not big fans of light, so your terrarium or plastic container should be kept in a dimly lit area. Under normal conditions isopods move about slowly and feed casually; however, there is a noticeable shift in their behavior when changes are made to moisture, temperature, light, and touch stimuli. Recommended products Wisconsin Fast Plants® These quick-developing Brassica rapa plants are excellent for use in many studies, particularly examinations of plant life cycles, inheritance of stem or leaf color, and maternal inheritance. Wisconsin Fast Plants® go from planted seed to seed in about 40 to 55 days, depending on experimental conditions. The plants grow quickly, emerging from a specially formulated soil in 2 to 3 days, and are ready for pollination at 11 to 14 days. They require a 24-hour light source provided by cool, white fluorescent bulbs; a constant water source; and consistent warm temperatures. There are several traits to choose from, including expression of purple coloration (anthocyanin), leaf hairs, yellow-green leaves, and dwarfism. Many supplies are reusable and inexpensive to replace. For project ideas and seed descriptions, visit our resources and the Wisconsin Fast Plants® Web site. Recommended products Wrapping up experiments Once you have tested your mastery of the scientific method, you may wonder what to do with your living specimen(s). Carolina provides living organisms for educational purposes only, and we do not advocate the release of specimens into local environments. We suggest that organisms be maintained in your classroom, donated to another classroom or your local natural science center, or disposed of humanely as a last resort. Read more here. Plan for success Proper planning is the key to completing a successful science project, and we hope the information provided makes finding the right subject less complicated. Please contact the Living Materials Department (800.334.5551) if you have more questions. Other related products |
