An example of color code use: Study of the link between taxonomic proximity and genomic signature proximity: The whole set of short oligonucleotide frequencies observed in a DNA (Deoxyri-boNucleic Acid) sequence is species-specific and is thus considered as a "genomic signature". 2,21 Moreover, a DNA segment as short as 1 Kb (kilobase) is sufficient to characterise the genomic signature of the species. As a consequence, genomic signature appears qualifying the "writing style" of the species. The genomic signature is species specific: