Co-occurrence network of significantly abundant species.

<p>A. Spearman correlation method. B. SparCC method. The nodes represent microbial species from the genus <i>Bacteroides</i> (green), <i>Bifidobacterium</i> (blue), <i>Faecalibacterium</i> (orange) and <i>Roseburia</i> (purple). The thickness of the edges represents the level of association depending on the value of Spearman’s correlation coefficient or the SparCC score respectively. Positive correlations are predicted to exist between species of Faecalibacterium and Roseburia, as shown in gray lines. Negative correlations are predicted to exist between species of Bacteroides and Bifidobacterium, as shown in red lines, except for (<i>Bacteroides pectinophilus</i>).