The population genomics of archaeological transition in west Iberia: Investigation of ancient substructure using imputation and haplotype-based methods

Abstract

We analyse new genomic data (0.05-2.95x) from 14 ancient individuals from Portugal distributed from the Middle Neolithic (4200-3500 BC) to the Middle Bronze Age (1740-1430 BC) and impute genomewide diploid genotypes in these together with published ancient Eurasians. While discontinuity is evident in the transition to agriculture across the region, sensitive haplotype-based analyses suggest a significant degree of local hunter-gatherer contribution to later Iberian Neolithic populations. A more subtle genetic influx is also apparent in the Bronze Age, detectable from analyses including haplotype sharing with both ancient and modern genomes, D-statistics and Y-chromosome

The Eastern side of the Westernmost Europeans: Insights from subclades within Y‐chromosome haplogroup J‐M304

“…Farming arrived in Portugal suddenly and at essentially the same time it occurred across the western Mediterranean, as revealed by the chronology of the earliest Neolithic sites in the country that are recorded since 6000 ya BC (García Puchol, Diez Castillo, & Pardo‐Gordó, ; Martins et al, ; Zilhão, ). A recent study (Martiniano et al, ) which sequenced 14 ancient genomes from Portugal ranging from the Middle Neolithic to the Middle Bronze Age reported the existence of Y‐chromosomal subclades G2 and I2, but not J. This finding stands in contrast to inferences made on the basis of modern data, which advocated for an earlier spread of J lineages coinciding with the propagation of agriculture.…”

“…The timing and distribution of J1a2b‐P58 were associated with demic expansion of Neolithic agriculturalists and hunter‐gatherers into the Arabian Peninsula from the fertile‐crescent (Al‐Zahery et al, ; Chiaroni et al, ). However, its near absence in ancient Neolithic Europeans, including those from Portugal (Martiniano, Cassidy, & O'Maolduin, ), together with its rise in frequencies in West Eurasia during and after the Bronze Age, suggest instead that its dispersion in Europe was mediated by other different migration episodes of the continent demographic history (Jobling & Tyler‐Smith, ; Kivisild, ).…”

“…The emergence of J2a‐derived lineages in the Bronze Age (Gamba et al, ; Kivisild, 2017) lends additional support to the hypothesis of a Bronze Age era dispersion of this lineage (Voskarides et al, ). The Y‐chromosomes identified in a small sample of three Middle Bronze Age individuals from Portugal belong to R1b‐P312 (Martiniano et al, ), currently the most common clade in Western Europe, and suggests that the main expansions of J lineages into Iberia are unlikely to have occurred prior to the Late Bronze Age.…”

Los peligros de la genética: investigación científica, periodismo de ciencia y conflicto interdisciplinar a la luz de una reciente polémica sobre Arqueología en España y Portugal.

“…Comencemos con una curiosidad: el genetista Rui Martiniano, firmante del manifiesto que nos ocupa, es también coautor del primer gran estudio arqueogenético sobre la Edad del Bronce ibérica, y el único publicado cuando estalló la polémica que nos ocupa (Martiniano et al, 2017). Este estudio, que por algún motivo no trascendió a los medios españoles, sí fue dado a conocer hace un par de años en un muy documentado y didáctico artículo de Teresa Firmino para el diario portugués Público, lo cual no pareció molestar a nadie en su momento, pese a que -y esto sí que es curioso-aludiera a "invasiones" en su propio título.…”

Veinte años de arqueología de la Prehistoria tardía en la Península Ibérica. Mirando hacia atrás y hacia adelante

“…Postcranial fractures were found on the skeletons of children from the Argaric site of Castellón Alto (Granada) (Jiménez-Brobeil et al 2006), which were likely incurred by falling from steep slopes at the site. DNA studies are shedding new light on the demographic dynamics of late prehistoric populations of Iberia (Fernández et al 2010;Lacan et al 2011;Gamba et al 2012;Hervella et al 2012;Carvalho et al 2016;Martiniano et al 2017;Szécsényi-Nagy et al 2017). techniques have been used to study the painted rock art of Levantine Spain and Portugal (Montero et al 1998;Rogerio et al 2011).…”