Exploit microbes for the future of humanity

In 1992, the Union of Concern Scientists in Washington DC and more than 1,700 researchers published the World Scientists' Warning to Humanity. He warned that human beings inflicted "harsh and often irreversible damage" to the environment and that current practices endangered the future of humankind. To date, more than 21,000 scientists have endorsed a second widely circulated and published warning published in 2017.

This week, part of the Scientists Warning movement draws attention to a factor that has been largely ignored: microbes. In a consensus statement published in Nature Microbiology Reviews, 33 world-renowned microbiologists "warn humanity" that the impact of climate change will depend to a large extent on the reaction of microorganisms (R. Cavicchioli et al. et al. Nature Rev. Microbiol. https://doi.org/10.1038/s41579-019-0222-5; 2019).

The ubiquity and diversity of bacteria, archaea, viruses, fungi and protozoa have only been appreciated in recent decades. Researchers recognize the colossal number (about 10³⁰ total bacteria and archaea) and the range of microorganisms, and that they are essential to the food web and the carbon cycle and other elements. Microorganisms can accelerate the release of greenhouse gases from melting permafrost, and climate change increases the spread of infectious diseases that threaten public health and food security.

The consensus statement provides for the first time a consolidated global vision of the reciprocal effects of micro-organisms and climate change. It highlights the potential for controlling microbes to mitigate global warming, for example through their role in producing biofuels from managed wetlands. The group calls for long-term monitoring of microbial activities relevant to greenhouse gas fluxes; this will require dedicated funding and international collaboration.

Microbiologists are poorly represented on the advisory and executive committees that decide on global environmental and public health policies. Their expertise and advice must be included to help prioritize future actions to mitigate climate change. The authors of the declaration call for the integration of microbiology into the United Nations Sustainable Development Goals. (Only one, in good health, explicitly lists microorganisms in its targets and indicators.) As the most abundant organism on the planet, it is time for microbes to become more visible.