Fig. 9

Biogeographic association between viral contigs and Ca. Chlorobium antarcticum CRISPR spacers. The schematic depicts the Vestfold Hills and Rauer Islands systems that were the sources of the viral contigs that matched to Ca. Chlorobium antarcticum CRISPR spacers (Additional file 1: Table S11). Lines (red or blue) connect an aquatic system where CRISPR-spacers were identified to a system where matching viral contigs were identified. The width of a line (red or blue) approximates the number of spacer-viral contig matches. The dark blue end of a line (red or blue) denotes the system that was the source of the viral contigs, with the other end of the line being the source of the Ca. Chlorobium antarcticum CRISPR-spacers. Spacer-viral contig matches within the three systems harbouring Ca. Chlorobium antarcticum (AL, EF, and TB; red lines) are distinguished from spacer-viral contig matches between AL, EF, or TB, and the other aquatic systems in the Vestfold Hills and Rauer Islands (blue lines). Sources of Ca. Chlorobium antarcticum spacers are denoted by large circles: AL (), EF (), and TB (); other lakes are denoted by small circles (). Sources of viral contigs included: AL, DL (Deep Lake), CL (Club Lake), OL (Organic Lake), RL(F) (Rauer Lakes from Filla Island: RL2, 3, 11), RL(T) (Rauer Lakes from Torckler Island: RL5, 6, 13). The location of the systems relative to each other is shown approximately to scale