 Biogeochemical cycles are what make the planet “function” in any sense. On Earth today, carbon, oxygen, and nitrogen cycles are particularly obvious. These cycles are interdependent, and display a degree of stability over geological time (e.g., oxygen has made up 21% of the Earth’s atmosphere for almost half a billion years, despite extraordinary fluctuations in lifeforms and physical features of the planet such as temperature). Although geological processes sustain such cycles over very long timescales, the world humans experience is largely a product of far more rapid microbial interactions. Microbes “run” most of these cycles as they generate energy from chemical compounds and light (Falkowski et al. 2008; Jelen et al. 2016). Microorganisms prevail even when they comprise less of the biomass involved than macroorganisms participating in the same process. For example, plants form the physical bulk of organisms involved in carbon and oxygen cycles (Bar-On et al. 2018), but a large amount of that biomass is made up of non-living material in woody plants. This material is often called “heartwood”, and it does not contribute actively to biogeochemical cycles (Chattaway  1952).[4]  In fact, the very tendency of microbes not to hoard elements in the form of biomass and instead, to have a high turnover of metabolizing populations (Strom 2008; Zimmerman et al. 2020), could explain in part why there are fairly rapid biogeochemical cycles on the planet rather than long-term chemical sinks.