Fig. 3

Two-dimensional PCoA (unweighted UniFrac distances) plots for the gut (A) and the skin (C) ASVs of A. neomexicanus from SBluG (magenta), A. neomexicanus from SNW (blue-purple), A. marmoratus (blue), and A. inornatus (red). Triangle plots of the hybrid mean microbiota for the gut (B) and skin (D) ASVs based on unweighted UniFrac distances. The position of the hybrid microbiota projection (x-axis) represents a measure of the distance between the hybrid and each progenitor along the main axis of parental variation, while the height of the triangle (y-axis) represents the deviation of the mean hybrid microbiota relative to main axis of parental variation. All values are calculated in the “microbiota space” defined by the first 20 principal coordinates (> 95% of variance) and normalized by the distance between progenitors. Large circles are the mean value of 50 subsamples on observed data, and small circles represent the outcome of each individual subsample on observed data. Large triangles are the mean value of 50 subsamples on null models, and small triangles represent the outcome of each individual subsample on a null model. For observed data, we considered the A. neomexicanus populations from both locations (purple), only the A. neomexicanus location from SNW (blue-purple), and only the A. neomexicanus location from SBluG (magenta). For null models, we consider subsamples of the A. inornatus population (red), subsamples of the A. marmoratus population (blue), and samples based on combining A. inornatus + A. marmoratus individuals (periwinkle). For both observed data and null models, subsamples consisted of 12 randomly sampled individuals from each progenitor population (see the “Materials and methods” section). Additional triangle plots can be found in Additional file 5; additional ordination plots can be found in Additional file 3