Warmer and drier ecosystems select for smaller bacterial genomes in global soils

Bacterial genome size reflects bacterial evolutionary processes and metabolic lifestyles, with implications for microbial community assembly ecosystem functions. However, to understand the extent of genome-mediated responses environmental selections, we require studies that observe distributions along gradients representing different conditions soil bacteria normally encounter. In this study, used surface soils collected from 237 sites across globe analyzed how (e.g., carbon nutrients, aridity, pH, temperature) affect occurrences at level using profiling. We a joint species distribution model quantify effects environments on found aridity was major regulator warmer drier selecting smaller genomes. Drought-induced physiological constraints growth water scarcity cell metabolisms) may have led these correlations. This finding suggests increasing cover by ecosystems result in simplifications reduction size.