Fig. 4.

Neutrality plot analysis of eight red algae between GC12 (the mean GC content at the first and second positions) and GC3 (GC content at the third codon position). The black solid line represents the correlation line, and the equation of the correlation line is shown below the plot. The red dots represent the high-bias genes, the blue dots represent the medium-bias genes, and the green dots represent the low-bias genes. A: unicellular red algal group; B: multicellular red algal group