The non-universality of the genetic code.
D000818:Animals; D005075:Biological Evolution; D003062:Codon; D004272:DNA, Mitochondrial / Q000235:genetics*; D005815:Genetic Code; D012343:RNA, Transfer / Q000235:genetics; D013045:Species Specificity
D003062:Codon; D004272:DNA, Mitochondrial; D012343:RNA, Transfer