Fig. 1
From: Low microbiome diversity in threatened amphibians from two biodiversity hotspots
Association between skin bacterial diversity and threat status of amphibian species in two geographically distinct biodiversity hotspots. A, B Piecewise structural equation models accounting for environmental, host, and methodological factors. Amphibian skin bacterial diversity was estimated as number of detected sub-operational taxonomic units (sOTUs). Numbers are standardized coefficients (*p < 0.05). Unsupported paths shown as gray arrows were removed to improve model fit. Red arrows indicate the correlation of interest between host skin bacterial diversity and host threat status. Black arrows indicate other paths that were retained in the final pruned models. C, D Average skin sOTU richness between threatened (red) and non-threatened (gray) species. Threatened species carried lower skin sOTU richness in (C) Brazil’s Atlantic Forest (t = − 2.407, df = 15.436, p = 0.029) and D Madagascar (t = − 2.894, df = 131.981, p = 0.004). Error bars represent standard error