Inverting the planetarium: Symbiosis as an immersive performance for communicating microbial biodiversity loss

Communicating the loss of human gut microbial diversity is difficult: the organisms are invisible, culturally linked to disease, and lack the charismatic appeal of macroscopic conservation icons. We report the design and an embedded audience evaluation of Symbiosis, an immersive performance that integrates live cello, electronic composition, videomicrography, and full-dome planetarium projection around a narrative on the evolutionary connection between humans and gut microbes. Using an action-research approach, the work was developed and adapted over five stagings between July 2023 and May 2026: a premiere at the First European Planetary Health Congress, three adaptations for documentary, music-festival, and public-festival audiences, and a forty-minute version coupled to the launch of the Feed Your Microbes citizen science campaign, which framed dietary fibre and fermented foods as the practical route to restoring gut microbiota. The fifth staging carried a pre-specified embedded evaluation comprising a paired pre/post questionnaire (53 paired records) and a citizen science enrolment endpoint. Self-reported familiarity with the gut microbiome rose from a paired mean of 2.38 to 3.15 (Wilcoxon signed-rank W = 11.5, p  < 0.001); 86% of post-survey respondents agreed that increasing dietary fibre is beneficial for health, and 62% reported being likely to enrol in the campaign. The action-oriented closing act was most often named as memorable (43%), while the central mourning act, a requiem for a microbe, produced a more moderate emotional response. We conclude that inverting the planetarium, turning its full dome toward the microbial world, and coupling an affective experience to behavioural change, is a transferable strategy for planetary health communication.