Ancient DNA evidence for the ecological globalisation of cod fishing in medieval and post-medieval Europe

Abstract

33 Understanding the historical emergence and growth of long-range fisheries can provide 34 fundamental insights into the timing of ecological impacts and the development of coastal bioRxiv preprint doi: https://doi.org/10.1101/2022.06.03.494519; this version posted June 5, 2022. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC-ND 4.0 International license. 35 communities during the last millennium. Whole genome sequencing approaches can improve 36 such understanding by determining the origin of archaeological fish specimens that may have 37 been obtained from historic trade or distant water. Here, we used genome-wide data to 38 individually infer the biological source of 37 ancient Atlantic cod specimens (ca. 1050 to 1950 39 CE) from England and Spain. Our findings provide novel genetic evidence that eleventh- to 40 twelfth-century specimens from London were predominantly obtained from nearby 41 populations, while thirteenth- to fourteenth-century specimens derived from distant sources. 42 Our results further suggest that Icelandic cod was exported to London earlier than previously 43 reported. Our observations confirm the chronology and geography of the trans-Atlantic cod 44 trade from Newfoundland to Spain starting by the early sixteenth century. Our findings 45 demonstrate the utility of whole genome sequencing and ancient DNA approaches to describe 46 the globalisation of marine fisheries and increase our understanding regarding the extent of the 47 North-Atlantic fish trade and long-range fisheries in medieval and early modern times. 48 49 Key words: cod trade, historical ecology, marine fisheries, zooarchaeology, biological source 50 51