Figure 7

Correlation between Codon Bases in Codons of 113 Species. The frequency of the four possible nucleotide bases (A, T, G, G) in the 3 possible codons positions (1^st. 2^nd, 3^rd) were counted in 113 codon usage tables and plotted against each other. A1+T1 > A3 means the correlation between the sum of the 1^st A plus 1^st T frequencies and the 3^rd A frequency (n = 113).