SAR11's * plan to take over the ocean (and then the world!) is discovered by the human invention of metagenomic** sequencing.
*SAR11 - a group of microbes that is found in thousands of ocean samples from all over the globe. It is also now known to inhabit freshwater systems as well. What are you planning, you naughty microbes?
**Metagenomic sequencing is a type of DNA sequencing that examines bacterial communities straight from environmental samples, no culturing or cloning needed! This way we get to see exactly what is there ... and how much of it.