Towards a taxonomy of microbial value.

Microbial life constitutes the vast majority of Earth’s biodiversity and drives the ecological processes upon which macroscopic life depends. Yet microbes remain neglected in environmental ethics (Wienhues 2022) and in global biodiversity and conservation initiatives (Junker and Farwig 2025). In this paper, I argue that this institutionalised exclusion reflects an entrenched ethical bias toward macroscopic life. To challenge this bias, I turn to Muraca’s relational axiology (2011, 2016), which rejects the intrinsic–instrumental value dichotomy and instead posits forms of value based on relational loci of co-constitution. Muraca distinguishes fundamental-relational values, grounded in identity-constituting relations, from functional-relational values, grounded in the roles organisms perform towards certain ends.

I argue that microbial assemblages exemplify fundamental-relational value. They are not merely background conditions - they are metabolic constituents of flourishing. Gut microbiomes shaping cognition, mycorrhizal fungi structuring forest resilience, and coral-algal-bacterial symbioses enabling persistence under climate stress all demonstrate how microbial relations are formative of flourishing across scales. Microbes, I will argue, also bear functional-relational value given their contributions as necessary means to both ecological dynamics (e.g., in coral reefs) and cultural practices (e.g., Koji fermentation).

The upshot will be that applying Muraca’s axiology to microbial life offers a promising remedy for the deep macroscopic bias in biodiversity thought; however, her taxonomy requires some expansion. To account for microbial value comprehensively, I introduce process-relational value as a category alongside fundamental-relational and functional-relational value.

Whereas functional-relational value concerns plausibly replaceable roles, process-relational value captures the contributions of necessary means whose participation in unfolding ecological processes is non-fungible and constitutive of the process’s integrity. For example, the role of coral polyps in the construction and maintenance of coral reefs is not reducible to a multiply realisable function but represents continuous participation as a necessary means in the dynamics of the greater whole (the reef).

With an expanded Muracarian axiology in place, I explore how a microbially-inclusive environmental ethic could overcome the macroscopic bias and inform biodiversity initiatives, e.g., by integrating microbiome health into monitoring frameworks such as the UN’s Global Environment Monitoring System.

 

Please consider this abstract for Philosophies of Biodiversity Conservation (TRA4).