Fig. 1

The tripartite fungus-farming symbiosis is complete after environmental acquisition of the fungal cultivar. A: Schematic of the tripartite symbiosis and the contributions from the termite host and symbiotic microbial partners to digestion and degradation of plant biomass. For a detailed description of the biomass degradation process, see [27]. Photos used with permission from Saria Otani. B: Assembly of the symbiosis over colony development and experimental timepoints. Laboratory colonies with inherited bacteria present in the guts of the royal pairs and workers prior to fungus acquisition (Pre-fungus), laboratory colonies once the fungus has been acquired (Post-fungus), and mature field colonies (Field). The gradual darkening of the gut illustrates the maturation of the gut microbiome with time, where the worker microbiome increases and the royal pair microbiome decreases in complexity