To demonstrate taxonomic distribution at decreasing ranks, the data were split according to different logarithmic abundance ranges as appropriate. The low abundance orders comprising the “Other” category included Synergistales, Halanaerobiales, Mycoplasmatales, Xanthomonadales, Sphingobacteriales, Caulobacterales, Desulfobacterales, Legionellales, Oceanospirillales, Deinococcales, Methanobacteriales, Myxococcales, Anaerolineales, Methylophilales, Chromatiales, Thermales, Bdellovibrionales, Desulfuromonadales, Solirubrobacterales, Methanomicrobiales, Planctomycetales, Methylococcales, Anaeroplasmatales, Coriobacteriales, Desulfovibrionales, Rhizobiales, Rhodocyclales, Sphingomonadales, Victivallales. Plots for subjects 2–4 are available in Figures S5.