Biofilm closeup (IMAGE) Dartmouth College Caption Dartmouth researchers explored how bacteria species coexist in communities known as biofilms, which can cause serious infections and are notoriously difficult to treat. This microscopy image shows a biofilm with the three bacterial species the researchers studied: Pseudomonas aeruginosa (yellow), Escherichia coli (pink/purple), and Enterococcus faecalis (blue/green). The found that P. aeruginosa dominates the other species before receding when the host surface becomes too crowded. When the other species surge, the dominant bacteria returns. Credit Carey Nadell Usage Restrictions N/A License Original content 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.