moderately significantp < .05
The correlation analysis between GC12 and GC3 showed that there was a highly significant correlation ( p < .01) between GC12 and CG3 of ATP6 , COX1 , CYTB , ND2 , ND5 , and ND6 genes, as well as a moderately significant correlation for ATP8 ( p < .05), indicating that the mutation pattern of bases in codon positions one and two was identical to that of position three and that mutational pressure played a significant role in the CUB of these seven genes.