Figure 2.

Phylogenetic diversity across ocean samples. (a) Maximum likelihood phylogeny using core genes from 41 Prochlorococcus strains, 2 Prochlorococcus metagenomic assemblies and 15 Synechococcus strains. Bootstrap values out of 100 resamplings are indicated by circles, filled in have 100% support and empty have at least 50% support. (b) Heatmap of samples versus the clades denoted in the phylogeny, c1–c13, and deep phylogenetic group(s), g14–g18. Relative abundances of sequences were log transformed and clustered hierarchically. (c) Prochlorococcus phylogenetic variation across metagenomic sites clustered using Bray–Curtis dissimilarity of PPlacer placed sequences for samples passing a 500-sequence threshold and rarefied. Node values are bootstrap support for the clade out of 100 resamplings, with filled in circles representing >75% support and empty circles representing >25% support for the group. Sample sites are color coded by region (Figure 1).