Clustering of oral biofilm samples according to the estimated microbial diversity. Log2 transformed frequencies of top 40 genera found in the dental plaque metatranscriptome through time are shown. Metatranscriptome samples were identified with MT prefix followed by time point (6, 12, 24, or 48 hours of biofilm formation). Number after dot refers to donor code. Bacterial genera labels are highlighted in colour according to phylum: Actinobacteria (pink), Bacteroidetes (Orange), Fusobacteria (Green), Firmicutes (Blue), Proteobacteria (Black), and Spirochaetes (Grey).