0000000000797721
AUTHOR
Brendan J. Culleton
Reconstructing the deep population history of Central and South America
We report genome-wide ancient DNA from 49 individuals forming four parallel time transects in Belize, Brazil, the Central Andes, and the Southern Cone, each dating to at least ∼9,000 years ago. The common ancestral population radiated rapidly from just one of the two early branches that contributed to Native Americans today. We document two previously unappreciated streams of gene flow between North and South America. One affected the Central Andes by ∼4,200 years ago, while the other explains an affinity between the oldest North American genome associated with the Clovis culture and the oldest Central and South Americans from Chile, Brazil, and Belize. However, this was not the primary sou…
The genomic history of the Iberian Peninsula over the past 8000 years
We assembled genome-wide data from 271 ancient Iberians, of whom 176 are from the largely unsampled period after 2000 BCE, thereby providing a high-resolution time transect of the Iberian Peninsula. We document high genetic substructure between northwestern and southeastern hunter-gatherers before the spread of farming. We reveal sporadic contacts between Iberia and North Africa by ~2500 BCE and, by ~2000 BCE, the replacement of 40% of Iberia's ancestry and nearly 100% of its Y-chromosomes by people with Steppe ancestry. We show that, in the Iron Age, Steppe ancestry had spread not only into Indo-European-speaking regions but also into non-Indo-European-speaking ones, and we reveal that pre…
The Arrival of Steppe and Iranian Related Ancestry in the Islands of the Western Mediterranean
A series of studies have documented how Steppe pastoralist-related ancestry reached central Europe by at least 2500 BCE, while Iranian farmer-related ancestry was present in Aegean Europe by at least 1900 BCE. However, the spread of these ancestries into the western Mediterranean where they have contributed to many populations living today remains poorly understood. We generated genome-wide ancient DNA from the Balearic Islands, Sicily, and Sardinia, increasing the number of individuals with reported data from these islands from 3 to 52. We obtained data from the oldest skeleton excavated from the Balearic islands (dating to ∼2400 BCE), and show that this individual had substantial Steppe p…
Nanodiamond-Rich Layer across Three Continents Consistent with Major Cosmic Impact at 12,800 Cal BP
© 2014 by The University of Chicago. All rights reserved. A major cosmic-impact event has been proposed at the onset of the Younger Dryas (YD) cooling episode at ≈12,800 ± 150 years before present, forming the YD Boundary (YDB) layer, distributed over 150 million km2 on four continents. In 24 dated stratigraphic sections in 10 countries of the Northern Hemisphere, the YDB layer contains a clearly defined abundance peak in nanodiamonds (NDs), a major cosmic-impact proxy. Observed ND polytypes include cubic diamonds, lonsdaleite-like crystals, and diamond-like carbon nanoparticles, called n-diamond and i-carbon. The ND abundances in bulk YDB sediments ranged up to ≈500 ppb (mean: 200 ppb) and…
Reply to Holliday and Boslough et al.: Synchroneity of widespread Bayesian-modeled ages supports Younger Dryas impact hypothesis
Holliday (1) rejects age-depth models for the Younger Dryas boundary layer (YDB) in Kennett et al. (2), claiming that they are incorrect for several reasons, including age reversals, high age uncertainties, and use of optically stimulated luminescence (OSL) dating. These same claims previously were presented in Meltzer et al. (3) and were discussed and refuted in Kennett et al. (2). These criticisms apply to nearly all dated archaeological and geological sequences, including the Odessa meteorite impact crater, where paradoxically, Holliday et al. (4) modeled an impact age using OSL dating (>70% of dates used) with large uncertainties (to >6,000 y) and age reversals (>40% of dates are revers…
The spread of steppe and Iranian-related ancestry in the islands of the western Mediterranean
Steppe-pastoralist-related ancestry reached Central Europe by at least 2500 bc, whereas Iranian farmer-related ancestry was present in Aegean Europe by at least 1900 bc. However, the spread of these ancestries into the western Mediterranean, where they have contributed to many populations that live today, remains poorly understood. Here, we generated genome-wide ancient-DNA data from the Balearic Islands, Sicily and Sardinia, increasing the number of individuals with reported data from 5 to 66. The oldest individual from the Balearic Islands (~2400 bc) carried ancestry from steppe pastoralists that probably derived from west-to-east migration from Iberia, although two later Balearic individ…
The genomic history of the Iberian Peninsula over the past 8000 years
We assembled genome-wide data from 271 ancient Iberians, of whom 176 are from the largely unsampled period after 2000 BCE, thereby providing a high-resolution time transect of the Iberian Peninsula.We document high genetic substructure between northwestern and southeastern hunter-gatherers before the spread of farming.We reveal sporadic contacts between Iberia and North Africa by ~2500 BCE and, by ~2000 BCE, the replacement of 40% of Iberia's ancestry and nearly 100% of its Y-chromosomes by people with Steppe ancestry.We show that, in the Iron Age, Steppe ancestry had spread not only into Indo-European-speaking regions but also into non-Indo-European-speaking ones, and we reveal that presen…
Bayesian chronological analyses consistent with synchronous age of 12,835-12,735 Cal BP for Younger Dryas boundary on four continents
The Younger Dryas impact hypothesis posits that a cosmic impact across much of the Northern Hemisphere deposited the Younger Dryas boundary (YDB) layer, containing peak abundances in a variable assemblage of proxies, including magnetic and glassy impact-related spherules, high-temperature minerals and melt glass, nanodiamonds, carbon spherules, aciniform carbon, platinum, and osmium. Bayesian chronological modeling was applied to 354 dates from 23 stratigraphic sections in 12 countries on four continents to establish a modeled YDB age range for this event of 12,835-12,735 Cal B.P. at 95% probability. This range overlaps that of a peak in extraterrestrial platinum in the Greenland Ice Sheet …
AMS DATING OF HUMAN BONE FROM COVA DE LA PASTORA: NEW EVIDENCE OF RITUAL CONTINUITY IN THE PREHISTORY OF EASTERN SPAIN
We present the results of 10 AMS radiocarbon dates for Cova de la Pastora (Alcoi, Alicante), a burial cave attributed to the Late Neolithic/Chalcolithic in eastern Spain. The direct dating of 10 human mandibles from Cova de la Pastora indicates that the cave was used as a burial place from the Late Neolithic/Chalcolithic to the Bronze Age. These dates reveal a continuity of ritual use not previously identified at the site. This case also serves to highlight the utility of revisiting historic excavations and museum collections with modern techniques to shed new light on the prehistoric human record.
Osteological and paleodietary investigation of burials from Cova de la Pastora, Alicante, Spain
We present results of osteological and isotopic analyses of human remains from Cova de la Pastora (Alcoi, Alicante, Spain) and discuss the implications in light of a new sequence of radiocarbon dates indicating that the cave was used as a burial site in the Late Neolithic (ca. 3800e3000 cal BC), Chalcolithic (ca. 3000 e2500 cal BC), Bell Beaker Transition (Horizonte Campaniforme Transicional - HCT; ca. 2500e2200 cal BC) and the Bronze Age (ca. 2200e1500 cal BC). Similarities in stable isotopic values of C and N indicate little variation in subsistence between men and women, and a similar nutritional base from the Late Neolithic to the Bronze Age. This pattern of stability is augmented by ev…