Figure 2From: Bacterial communities on classroom surfaces vary with human contactSurfaces harbored significantly different bacterial communities and were linked to differential human contact. (a) Bacterial communities were constrained by four different surface types using distance-based redundancy analysis (DB-RDA; constrained inertia = 11.4%) and were significantly different among types based on Canberra taxonomic distances (P = 0.001 from permutational multivariate analysis of variation). (b) Bacterial operational taxonomic units (OTUs) from DB-RDA are shown weighting communities in the same four primary directions. The first and second axes from DB-RDA are used in both ordinations (CAP 1 and CAP 2) . The strongest ten weighting OTUs for each surface type are highlighted if they were also significant indicator OTUs (all P values <0.05). (c) All samples were compared to potential source environments using principal components analysis (PCA), and the first principal component (37.8% of variance explained) was used as a surrogate for community similarity to either phyllosphere or human skin bacterial communities. Boxplots delineate (from bottom) minimum value, Q1, median (Q2), Q3, maximum value; notches approximate 95% confidence around median value, and outliers fall outside of the quartile range. Letters above each box indicate significant groupings after Tukey’s hones significant difference (HSD) test (adjusted P value <0.05).Back to article page