Fig. (2) Nucleotide relationships in normalized vertebrate mitochondrial
values. The vertical axis represents G, C, T and A contents
of the non-coding region on graphs A, B, C and D, respectively.
The horizontal axis represents G content of the complete
mitochondrial genome. Green and blue represent terrestrial and
aquatic vertebrates, respectively. Statistical differences between
terrestrial and aquatic vertebrates were evaluated using a student’s
t-test. G content in the complete mitochondrial genome, p < 0.01,
and in the coding region, G content; p < 0.01, C content; p > 0.05, T
content; p < 0.05, A content; p < 0.01.