Figure 3: Habitat-specificity of bacterial groups found in this study.
From: Marine mammals harbor unique microbiotas shaped by and yet distinct from the sea

(a) Relative OTU abundance in the pyrosequencing data set. Specimens with ⩾372 reads (n=199; single time point per animal; same specimens and order as in Fig. 1) are shown in columns, and OTUs with ⩾20 reads (n=236) are shown in rows. The OTUs are clustered using an NMDS sorting based on Bray–Curtis distance, while the specimens (shown in columns) are sorted per specimen group. Relative abundance is shown in grey scale (white, absent; black, high abundance). (b) Venn diagram showing sharing of the 4,137 OTUs found in a rarefied pyrosequencing data set of 18 dolphins, 18 sea lions and 18 water specimens. Each data set was rarefied to 69,377 reads to match the smallest data set (from the water samples). Green, dolphins (1,452 OTUs total, includes oral, gastric, and rectal specimens from MMP and wild dolphins); red, sea lions (659 OTUs oral, gastric, rectal); blue, seawater (2,212 OTUs). The overlap between the circles is not to scale. (c) Quantitative PCR on four specimen types. Results are presented as average gene copy number per millilitre for seawater and gastric fluid, or per swab for oral and rectal specimens, for each of four different qPCR tests. Each individual qPCR was done in triplicate, error bars indicate s.d.. The numbers above the bars indicate the number of specimens positive for each qPCR test.