When simulating future environmental conditions, researchers confront a problem: Laboratory experiments are easy to control and to reproduce, but are insufficient to mimic the complexity of natural ecosystems. In contrast, experiments under real conditions in nature are much more complicated and difficult to control. Scientist of the GEOMAR Helmholtz Centre for Ocean Research Kiel have combined both approaches to investigate the response of a major plankton species to increasing ocean acidification. The results have now been published in the international journal Nature Ecology and Evolution.