Fig. 4: Effects of geography and soil chemical properties on insect gut bacterial diversity.

a The sampling sites. For details of the sample collection information, see Supplementary Table 1. b The pH and organic carbon/total nitrogen contents (C/N) of soils from different sampling sites. The organic carbon contents and total nitrogen contents is presented in Supplementary Fig. S2. c Distance-based redundancy analysis (db-RDA) of the insect bacterial community with abiotic variables across different geographic areas. d The effect s of latitude, pH and C/N ratio of soils on the Chao1 richness of insect gut bacterial communities. e The effects of latitude, pH and C/N ratio of soils on the phylogenetic diversity of insect gut bacterial communities. The correlations are based on linear Pearson correlation and the significance of the correlation is at p < 0.05.