“…Low complexity, extremophilic consortia that thrive in acid mine drainage (AMD) environments have been proposed as a model system for the study of natural microbial communities (Denef et al, 2010b). Ecological interactions such as competition, mutualism, predation and synergism have been described in such environments (Johnson, 1998). AMD biofilm communities from the Richmond Mine at Iron Mountain, CA, USA have been well characterized using culture independent techniques (Edwards et al, 1999;Bond et al, 2000a, b;Druschel et al, 2004;Wilmes et al, 2008b), and have also been the subject of intensive genomic and proteomic studies (Tyson et al, 2004;Ram et al, 2005;Lo et al, 2007;Simmons et al, 2008;Denef et al, 2009), making them ideal for in-depth ecological analyses.…”