close
Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Nov 19;7(47):eabi7038.
doi: 10.1126/sciadv.abi7038. Epub 2021 Nov 17.

Genomic transformation and social organization during the Copper Age-Bronze Age transition in southern Iberia

Vanessa Villalba-Mouco  1   2   3 , Camila Oliart  4 , Cristina Rihuete-Herrada  4 , Ainash Childebayeva  1   3 , Adam B Rohrlach  1   3   5 , María Inés Fregeiro  4 , Eva Celdrán Beltrán  4 , Carlos Velasco-Felipe  4 , Franziska Aron  1 , Marie Himmel  1 , Caecilia Freund  1 , Kurt W Alt  6   7 , Domingo C Salazar-García  8   9   10 , Gabriel García Atiénzar  11 , Ma Paz de Miguel Ibáñez  11 , Mauro S Hernández Pérez  11 , Virginia Barciela  11 , Alejandro Romero  11   12 , Juana Ponce  13 , Andrés Martínez  13 , Joaquín Lomba  14 , Jorge Soler  15 , Ana Pujante Martínez  16 , Azucena Avilés Fernández  17 , María Haber-Uriarte  14 , Consuelo Roca de Togores Muñoz  15 , Iñigo Olalde  2   18 , Carles Lalueza-Fox  2 , David Reich  18   19   20   21 , Johannes Krause  1   3 , Leonardo García Sanjuán  22 , Vicente Lull  4 , Rafael Micó  4 , Roberto Risch  1   4 , Wolfgang Haak  1   3   23
Affiliations

Genomic transformation and social organization during the Copper Age-Bronze Age transition in southern Iberia

Vanessa Villalba-Mouco et al. Sci Adv. .

Abstract

The emerging Bronze Age (BA) of southeastern Iberia saw marked social changes. Late Copper Age (CA) settlements were abandoned in favor of hilltop sites, and collective graves were largely replaced by single or double burials with often distinctive grave goods indirectly reflecting a hierarchical social organization, as exemplified by the BA El Argar group. We explored this transition from a genomic viewpoint by tripling the amount of data available for this period. Concomitant with the rise of El Argar starting ~2200 cal BCE, we observe a complete turnover of Y-chromosome lineages along with the arrival of steppe-related ancestry. This pattern is consistent with a founder effect in male lineages, supported by our finding that males shared more relatives at sites than females. However, simple two-source models do not find support in some El Argar groups, suggesting additional genetic contributions from the Mediterranean that could predate the BA.

PubMed Disclaimer

Figures

Fig. 1.
Fig. 1.. Geographic locations as well as cultural and chronological information of the studied sites.
Map of Iberia with sites mentioned in the main text (table S1.1). The area shaded in teal highlights the maximum extent of EBA El Argar. Chronological time scale for published and new individuals analyzed in this study (bottom panel). Directly radiocarbon-dated individuals are plotted according to their mean calibrated date (2-sigma range), and jitter option within their specific time range was applied for individuals that were dated by archaeological context (table S2.1). Random jitter was applied to the Y axis to prevent overplotting.
Fig. 2.
Fig. 2.. Key population genetic analyses of CA groups.
(A) PCA of published and newly genotyped CA groups projected onto 2018 modern-day West Eurasians (gray dots). Ancient individuals projected and their correspondent labels are listed in table S2.1. (B) f4-statistics showing significant differences in terms of WHG ancestry in northern and southern CA groups (error bars indicate 3 standard errors) (table S2.2 also includes the results for MLN groups). (C) f4-statistics highlighting the higher affinity of southern CA Iberian groups to GoyetQ2 (error bars indicate 3 standard errors) (table S2.3). (D) Modeling Iberian MLN and CA without steppe-related ancestry with a three-way qpAdm admixture model using distal sources Anatolia_N, WHG, and GoyetQ2. Southern MLN and CA Iberian groups show an extra minor ancestry component represented by GoyetQ2 (error bars indicate 1 standard error; numbers in brackets are P values for qpAdm model) (table S2.4).
Fig. 3.
Fig. 3.. Evidence for steppe-related ancestry in EBA individuals from southeastern Iberia.
(A) West Eurasian PCA calculated with modern populations (gray dots) (23) on which relevant ancient CA, Bell Beaker and BA groups discussed in the text were projected (correspondent labels are listed in table S2.1).(B) f4-statistics showing the increased affinity to Yamnaya_Samara (absent in CA individuals), which implies the presence of steppe-related ancestry in EBA Iberians. This plot also shows the almost-complete turnover in Y-chromosome lineages in male individuals (color-filled squares) during the southeastern Iberian EBA (error bars indicate 3 standard errors) (table S2.6).
Fig. 4.
Fig. 4.. Modeling genetic ancestry in Iberian BA groups.
(A) Modeling Iberian BA individuals with steppe-related ancestry as a two- and three-way qpAdm admixture model using proximal sources C_Iberia_CA/SE_Iberia_CA, Germany_Bell_Beaker, and Iran_C (table S2.11). (B) Modeling Iberian BA individuals with steppe-related ancestry as a two- and three-way qpAdm admixture model using proximal sources C_Iberia_CA_Stp, C_Iberia_CA/SE_Iberia_CA, and Iran_N (table S2.1). P values for each group are given inside each column. Faded colors indicate rejected models when applying a P value cutoff of ≤0.05.
Fig. 5.
Fig. 5.. Summary of genetic analyses that explore the genetic outlier status of individual ZAP002.
(A) f4-statistics to detect Basal Eurasian ancestry and/or African ancestry. Cladality test with ZAP002 and individuals from the site La Almoloya (ALM) and a set of test populations including Africans and Near Eastern (NE) groups, and chimpanzee in the outgroup. The results show that only Moroccan, Iberomaurusian, and Mbuti show a shift toward positive f4-values (table S2.16). (B) f4-statistics to detect either high Basal Eurasian or North African ancestry in which negative values imply excess affinity to Mbuti (table S2.17). (C) Supported and nonsupported qpAdm admixture models for outlier individual ZAP002. On the left, C_Iberia_CA is located in the outgroups and the model finds support with Sicily EBA as a source, pointing to a nonlocal origin of individual ZAP002 (table S2.18).
Fig. 6.
Fig. 6.. Biological kinship and female-male dynamics at the site La Almoloya.
(A) Sum of all ROH segments measured with hapROH for CA and BA above 400,000 SNPs in 1240k panel (table S2.21). (B) qpAdm z scores between autosomes and the X chromosome showing no signal for male bias related to steppe ancestry in the model with distal sources (right) or proximal sources (left) (table S2.22). (C) f3-outgroup statistics of the form f3(female, female; Mbuti), f3(female, male; Mbuti), and f3(male, male; Mbuti), highlighting a closer relationship among males than among females or closer relationships whenever they involve at least one male individual (first- and second-degree related pairs are excluded from the calculation) (table S2.23). (D) PWMR values of individuals compared to the PWMR average of the site La Almoloya. Dashed lines indicate a lower PWMR average and, thus, higher pairwise relatedness in adult males than adult females (table S2.24).
See this image and copyright information in PMC

References

    1. Weiss H., Courty M.-A., Wetterstrom W., Guichard F., Senior L., Meadow R., Curnow A., The genesis and collapse of third millennium north Mesopotamian civilization. Science 261, 995–1004 (1993). - PubMed
    1. C. Kuzucuoǧlu, C. Marro, Sociétés Humaines Et Changement Climatique À la Fin Du Troisième Millénaire: Une Crise A-t-elle Eu Lieu en Haute Mésopotamie?: Actes Du Colloque de Lyon, 5–8 Décembre 2005 (Institut français d’études anatolienne Georges-Dumézil, 2007).
    1. H. Meller, H. W. Arz, R. Jung, R. Risch, 2200 BC—A Climatic Breakdown as a Cause for the Collapse of the Old World? (Tagungen des Landesmuseums für Vorgeschichte Halle, 12. Landesamt für Denkmalpflege und Archäologie Sachsen-Anhalt, Landesmuseum für Vorgeschichte, 2015).
    1. Haak W., Lazaridis I., Patterson N., Rohland N., Mallick S., Llamas B., Brandt G., Nordenfelt S., Harney E., Stewardson K., Fu Q., Mittnik A., Bánffy E., Economou C., Francken M., Friederich S., Pena R. G., Hallgren F., Khartanovich V., Khokhlov A., Kunst M., Kuznetsov P., Meller H., Mochalov O., Moiseyev V., Nicklisch N., Pichler S. L., Risch R., Rojo Guerra M. A., Roth C., Szécsényi-Nagy A., Wahl J., Meyer M., Krause J., Brown D., Anthony D., Cooper A., Alt K. W., Reich D., Massive migration from the steppe was a source for Indo-European languages in Europe. Nature 522, 207–211 (2015). - PMC - PubMed
    1. Allentoft M. E., Sikora M., Sjögren K.-G., Rasmussen S., Rasmussen M., Stenderup J., Damgaard P. B., Schroeder H., Ahlström T., Vinner L., Malaspinas A.-S., Margaryan A., Higham T., Chivall D., Lynnerup N., Harvig L., Baron J., Casa P. D., Dąbrowski P., Duffy P. R., Ebel A. V., Epimakhov A., Frei K., Furmanek M., Gralak T., Gromov A., Gronkiewicz S., Grupe G., Hajdu T., Jarysz R., Khartanovich V., Khokhlov A., Kiss V., Kolář J., Kriiska A., Lasak I., Longhi C., McGlynn G., Merkevicius A., Merkyte I., Metspalu M., Mkrtchyan R., Moiseyev V., Paja L., Pálfi G., Pokutta D., Pospieszny Ł., Price T. D., Saag L., Sablin M., Shishlina N., Smrčka V., Soenov V. I., Szeverényi V., Tóth G., Trifanova S. V., Varul L., Vicze M., Yepiskoposyan L., Zhitenev V., Orlando L., Sicheritz-Pontén T., Brunak S., Nielsen R., Kristiansen K., Willerslev E., Population genomics of Bronze Age Eurasia. Nature 522, 167–172 (2015). - PubMed