The microorganisms in action (IMAGE) Max Planck Institute for Marine Microbiology Caption Left: Microscopic visualisation of MOB (pink) and other microorganisms (blue) from Lake Zug using fluorescent probes. Right: Visualisation of heavy carbon atoms (13C) in the biomass of MOB as a sign of their activity using NanoSIMS. The warmer the colour, the more 13C was taken up by the bacterial cells and the more active they were. Credit Sina Schorn/Max Planck Institute for Marine Microbiology Usage Restrictions Only to be used in the context of this publication and citing the correct copyright. 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.