Daphnia pulex (water flea)
D. pulex is a small crustacean found in almost every permanent, eutrophic (nutrient rich) freshwater body
parthenogenic, sexual and asexual, female with rare males
Daphnia have been used as a model species for over 250 years for studies of “phenotypic plasticity, behavior, toxicology, the evolution of sexual and asexual reproduction, [and recently] genetic research has addressed a number of evolutionary questions” (Ebert 2005). Daphnia are ideal model organisms as “they are small, cheap, and very easy to keep alive in a laboratory environment. Their almost transparent shell makes their internal functions easier to study and they are very susceptible to changes in temperature, food supplies, or dissolved oxygen content in their environment” (Miller).
Big thanks to Shian Liau from Aquatic Ecology & Ecosystem Studies, UWA for supplying the stock cultures and algae and generous support for this project. Daphnia used in this project was caught by Shian from Lake Monger in Perth, WA