Fig. 4.—

Size and coding content of animal mitochondrial DNA. Colored bars indicate the average number of nucleotides coding for ribosomal RNA (blue), protein (red), transfer RNA (green), or noncoding (black) computed using all available complete mt-genome sequences published in the NCBI RefSeq database as of April 9, 2016. Gray error bars indicate the upper and lower boundaries of the 95% interquantile range for genome sizes (2.5th and 97.5th percentiles). The shaded portion of the red bar in Myxozoa indicates additional protein-coding genes likely present in these genomes, but not recognizable due to an extreme rate of sequence evolution.