The COI mitochondrial gene is present in all animal phyla and in a few
others, and is the leading candidate for species identification through DNA
barcoding. Calculating a generalized form of total correlation on publicly
available data on the gene yields distinctive information-theoretic descriptors
of the phyla represented in the data. Moreover, performing principal component
analysis on standardized versions of these descriptors reveals a strong
correlation between the first principal component and the natural logarithm of
the number of known living species. The descriptors thus constitute clear
information-theoretic signatures of the processes whereby evolution has given
rise to current biodiversity