Neolithic and Bronze Age migration to Ireland and establishment of the insular Atlantic genome

Abstract

The Neolithic and Bronze Age transitions were profound cultural shifts catalyzed in parts of Europe by migrations, first of early farmers from the Near East and then Bronze Age herders from the Pontic Steppe. However, a decades-long, unresolved controversy is whether population change or cultural adoption occurred at the Atlantic edge, within the British Isles. We address this issue by using the first whole genome data from prehistoric Irish individuals. A Neolithic woman (3343–3020 cal BC) from a megalithic burial (10.3× coverage) possessed a genome of predominantly Near Eastern origin. She had some hunter–gatherer ancestry but belonged to a population of large effective size, suggesting a substantial influx of early farmers to the island. Three Bronze Age individuals from Rathlin Island (2026–1534 cal BC), including one high coverage (10.5×) genome, showed substantial Steppe genetic heritage indicating that the European population upheavals of the third millennium manifested all of the way from southern Siberia to the western ocean. This turnover invites the possibility of accompanying introduction of Indo-European, perhaps early Celtic, language. Irish Bronze Age haplotypic similarity is strongest within modern Irish, Scottish, and Welsh populations, and several important genetic variants that today show maximal or very high frequencies in Ireland appear at this horizon. These include those coding for lactase persistence, blue eye color, Y chromosome R1b haplotypes, and the hemochromatosis C282Y allele; to our knowledge, the first detection of a known Mendelian disease variant in prehistory. These findings together suggest the establishment of central attributes of the Irish genome 4,000 y ago.

How old are bacterial pathogens?

“…Finding pure hpAsia2 in the Italian Alps 5000 years ago suggests that the admixture that led to hpEurope was even more recent than 5000 years. However, the human migrations that are known to have occurred since the Bronze age [28] do not include a potential wave of migrants who might have introduced hpNEAfrica throughout Western Eurasia.…”

The Beaker Phenomenon and the Genomic Transformation of Northwest Europe

“…145 We also generated 62 new direct radiocarbon dates (Extended Data Bronze Age Britain. We combined our data with previously published ancient DNA data [2][3][4][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] 150 to form a genome-wide dataset of 476 ancient individuals (Supplementary Table 1). The 151 combined dataset included Beaker-associated individuals from Iberia (n=20), southern France 152 (n=4), northern Italy (n=1), central Europe (n=56), The Netherlands (n=9) and Britain (n=19).…”

On Applications of Space–Time Modelling with Open-Source 14C Age Calibration

“…There is little consensus over their interpretation, as in addition to cooking and feasting, other functions such as bathing, dying and brewing have been postulated (ibid.). What is apparent, however, is that from their appearance in the Late Neolithic period (Early Neolithic burnt mounds are known too, but these seem culturally and temporally distinctive) until their disappearance in the Early Iron Age, morphologically similar burnt mounds were used on the Island, hinting at a very long-lived pattern of behaviour spanning many other cultural changes and perhaps even at least one population replacement at a genetic level (Cassidy et al 2016). The frequency that these sites were used can address important questions, namely (a) the periods that they were intensely used, (b) whether there were any hiatuses or fluctuations in-phase with other changes in the archaeological record, and (c) what circumstances brought about the abandonment of this type of site.…”