Figure 1

Nucleotide substitution sites in the rbc LS, COI , and ITS gene regions of the Saccharina japonica morphological forms. The numbers above the top sequence represent the position of segregating sites and the start of a deletion or insertion (see also Additional file 4). Nucleotides are numbered from the beginning of our sequence. Dots indicate the same nucleotide as the reference sequence. The hyphens represent deleted nucleotides. ▴ denotes a deletion; † denotes the absence of a deletion; ▼ denotes an insertion; ‡ denotes the absence of an insertion. The sample abbreviations are in the section "Methods". COR: S. coriacea. The underlined nucleotides in bold face show fixed differences between COR and the other sequences.