Often called water fleas, Daphnia are small crustaceans that are one of the most studied living organisms. They can be used to investigate the compound eye, digestive system, reproductive system, appendages used for movement and life cycle stages. They also make great experimental animals, commonly used in physiological studies, including the effects of drugs on heart beat rate and temperature on metabolism. They are an easy-to-grow food source for hydra and small fish. Science Resource Box's living culture usually contains adults with eggs, juveniles, and neonates.
Note: Culture contains approximately 30–40 organisms per container. One culture is sufficient for a class of 30 students.
How to care for Daphnia:
Top photo by Hajime Watanabe