Principal Coordinates comparing unsimulated (real) samples based on (a) unweighted UniFrac distances where trees are computed using ghost-tree, (b) weighted UniFrac distances where trees are computed using ghost-tree, (c) unweighted UniFrac distances where trees are computed using ghost-tree, 0-branch length-foundation, (d) weighted UniFrac distances where trees are computed using ghost-tree, 0-branch-length foundation, (e) unweighted UniFrac distances where trees are computed using ghost-tree, 0-branch-length extensions, (f) weighted UniFrac distances where trees are computed using ghost-tree, 0-branch-length extensions. Blue points are simulated and real human saliva samples, and red points are simulated and real restroom surface samples. Plots were made using EMPeror software [25]. (PDF 522Â kb)