Fig. 4

a, b – Relative abundances of the bacterial and archaeal phyla in the communities of the cave biofilms (phylum Proteobacteria is subdivided into classes). Only the phyla with the abundance of ≥ 1% in the analyzed samples are present; the other phyla are merged into the “Other” category. Classification of the ASVs was conducted against the Silva database (138.1 release) with 50% threshold. c, d – Core microbiome analysis based on relative abundance and sample prevalence of the bacterial and archaeal genera taxa in the biofilms of the Shulgan-Tash cave. Prevalence was assessed as ASV detected in the range from 50 to 100% samples