Pleodorina starrii (image) University of Arizona Caption Pleodorina starrii has an incomplete division of labor. Although the 12 small cells near the top of this colony only swim, the 20 larger cells both swim and reproduce. Credit Copyright 2008 Matthew Herron. Usage Restrictions This photo may only be used to illustrate a story about the research described in the accompanying news release, Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.