Roman Atlantic garum : DNA confirms sardine use and population continuity in north-western Iberia

The Romans were among the first societies to extensively exploit fish resources, establishing large-scale salting and preservation plants where small pelagic fish were fermented to produce sauces such as garum . Here, the authors demonstrate that, despite being crushed and exposed to acidic conditions, usable DNA can be recovered from ichthyological residues at the bottom of fish-salting vats. At third-century AD Adro Vello (O Grove), Galicia, they confirm the use of European sardines ( Sardina pilchardus ) and move beyond morphology to explore population range and admixture and reveal the potential of this overlooked archaeological resource.