Finding. Long-lived termites carry a stronger mitochondrial A>G mutational signature than their short-lived cockroach relatives, and that bias does not stop at silent sites. Synonymous composition, codon usage, and amino acids all shift in step. An ageing signature first named in mammals is visible in insect mtDNA and strong enough to leave a proteome footprint. How a species lives can be read in how its mitochondrial genome is allowed to change.
Why this paper matters
mtDNA is usually a barcode. This paper treats it as a dosimeter. If life history sets the mutagen, and the mutagen sets the spectrum, and the spectrum leaks into amino acids, then comparative mitogenomes are ecology, not only phylogeny.
The mammalian A>G ageing signature getting a cross-phylum test is the mitochondrial-desk hook. Universality is the hypothesis; termites versus cockroaches is the trial.
What they actually measured
mtDNA mutational spectra and compositional cascade (nucleotides, codons, amino acids) in termites versus non-termite cockroaches. Stronger A>G in termites, coordinated downstream shifts.
Phylogenetic independence and caste biology will make or break the life-history claim. The abstract does not show those controls.
How to read the score
High sixties. Comparative mtDNA evolution with a proteome-level claim. Confidence is medium. Score 68.
What to do with it
If you model mtDNA ageing signatures or insect longevity, pull the A>G counts and the amino-acid shifts. Do not infer that termite mitochondria “age better.” The directional implication is that ecological mutational pressure can reach the mitochondrial proteome.
