Marine bacterial and protist communities are differentially influenced by species sorting and dispersal limitation Wenxue Wu and Chih-hao Hsieh Institute of Oceanography, National Taiwan University Bacterial and protist communities are the two key components in marine microbial food webs. Even though they are both microbes, these two groups can be geographically structured in distinct manners due to their differences in organismal traits. For example, bacteria and protists do exhibit fine differences in body size, metabolic activity and dispersal potential, in spite of their comparable attributes (e.g., small body size and…