Temperature and the structure of the ocean microbiome
Combining ecological theory and (lots of) data, in this preprint we show that the slower-growing marine bacteria are universally favored by temperature. We estimated growth rates from the ribosomal RNA copy number and compute the abundance weighted mean copy number to describe the abundance distribution of fast and slow growers in a bacterial community. Doing this for several datasets reporting the composition of marine bacterial communities across seasons, latitude and depth, we were able to report a macroecological pattern: slower-growing taxa become more abundant where and when seawater temperatures are higher. This pattern is predicted by ecological theory and previously confirmed in laboratory experiments with pairs of bacterial species.
So, if you ever wonder if predictions coming from laboratory experiments and simple models can be tested in natural communities, the answer is YES! Last but not least: our findings provide a clear prediction for how marine communities would change in a warmer world.
I love this project for many reasons, but the main one is that the meeting with Clare and Carina, two amazing scientists and human beings, was the one thing I was looking for every week during the first months of the lockdown :)