The formation of human populations in South and Central Asia

By sequencing 523 ancient humans, we show that the primary source of ancestry in modern South Asians is a prehistoric genetic gradient between people related to early hunter-gatherers of Iran and Southeast Asia. After the Indus Valley Civilization’s decline, its people mixed with individuals in the southeast to form one of the two main ancestral populations of South Asia, whose direct descendants live in southern India. Simultaneously, they mixed with descendants of Steppe pastoralists who, starting around 4000 years ago, spread via Central Asia to form the other main ancestral population. The Steppe ancestry in South Asia has the same profile as that in Bronze Age Eastern Europe, tracking a movement of people that affected both regions and that likely spread the distinctive features shared between Indo-Iranian and Balto-Slavic languages

Performance and automation of ancient DNA capture with RNA hyRAD probes

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordData Availability: The datasets generated for this study can be accessed in the ENA (Accession Number PRJEB43744). The program for piloting the Opentrons OT-2 robot can be accessed at https://github.com/TomaszSuchan/opentrons-hyRAD.DNA hybridization-capture techniques allow researchers to focus their sequencing efforts on pre-selected genomic regions. This feature is especially useful when analyzing ancient DNA (aDNA) extracts, which are often dominated by exogenous environmental sources. Here, we assessed, for the first time, the performance of hyRAD as an inexpensive and design-free alternative to commercial capture protocols to obtain authentic aDNA data from osseous remains. HyRAD relies on double enzymatic restriction of fresh DNA extracts to produce RNA probes that cover only a fraction of the genome and can serve as baits for capturing homologous fragments from aDNA libraries. We found that this approach could retrieve sequence data from horse remains coming from a range of preservation environments, including beyond radiocarbon range, yielding up to 146.5-fold on-target enrichment for aDNA extracts showing extremely low endogenous content (20-30%), while the fraction of endogenous reads mapping on- and off-target was relatively insensitive to the original endogenous DNA content. Procedures based on two, instead of a single round of capture, increased on-target coverage up to 3.6-fold. Additionally, we used methylation sensitive restriction enzymes to produce probes targeting hypomethylated regions, which improved data quality by reducing post-mortem DNA damage and mapping within multicopy regions. Finally, we developed a fully automated hyRAD protocol leveraging inexpensive robotic platforms to facilitate capture processing. Overall, our work establishes hyRAD as a cost-effective strategy to recover a set of shared orthologous variants across multiple ancient samples.University Paul Sabatier IDEX Chaire d’ExcellenceCNRSEuropean Union Horizon 2020Russian Foundation for Basic Researc

Climatic or dietary change? Stable isotope analysis of Neolithic–Bronze Age populations from the Upper Ob and Tobol River basins

Dietary changes in the populations inhabiting southwest Siberia and northern Kazakhstan indicate concurrent changes in the economy, at the same time marking the beginnings of East–West interaction across northern Eurasia. The introduction of domestic animal species of Near Eastern origin, such as sheep and goat, dramatically changed the lives of the local population. Past palaeodietary research using stable isotope analysis has mainly focussed on pastoral populations of the Bronze Age period. It is crucial, however, to assess the diets of humans and animals from earlier periods (Neolithic/Chalcolithic) in order to understand the timing and nature of dietary change during the Bronze Age of southwest Siberia and northern Kazakhstan, in particular the possible contribution of environmental change influencing dietary shifts. In this paper, we report the results of stable isotope analysis on 55 human and 45 faunal samples from southwest Siberia (Upper Ob River) and northern Kazakhstan (Tobol River basin), ranging from the Neolithic to the Bronze Age. These data, combined with published human and faunal collagen results from the region as well as new accelerator mass spectrometer (AMS) radiocarbon dating results, indicate little change in animal diet over time, but a notable change in human diet at ca. 2500 cal. BC. The data allow us to determine the time when pastoralism came to the fore, with concomitant economic differences to the local population.</p

The evolution of dog diet and foraging: Insights from archaeological canids in Siberia

Research on the evolution of dog foraging and diet has largely focused on scavenging during their initial domestication and genetic adaptations to starch-rich food environments following the advent of agriculture. The Siberian archaeological record evidences other critical shifts in dog foraging and diet that likely characterize Holocene dogs globally. By the Middle Holocene, body size reconstruction for Siberia dogs indicates that most were far smaller than Pleistocene wolves. This contributed to dogs' tendencies to scavenge, feed on small prey, and reduce social foraging. Stable carbon and nitrogen isotope analysis of Siberian dogs reveals that their diets were more diverse than those of Pleistocene wolves. This included habitual consumption of marine and freshwater foods by the Middle Holocene and reliance on C4 foods by the Late Holocene. Feeding on such foods and anthropogenic waste increased dogs' exposure to microbes, affected their gut microbiomes, and shaped long-term dog population history

Widespread horse-based mobility arose around 2,200 BCE in Eurasia

This is the author accepted manuscript. The final version is available from Nature Research via the DOI in this recordData availability:All collapsed and paired-end sequence data for samples sequenced in this study are available in compressed FASTQ format through the European Nucleotide Archive under accession number PRJEB71445, together with rescaled and trimmed bam sequence alignments against the nuclear horse reference genomes. Previously published ancient data used in this study are available under accession numbers PRJEB7537, PRJEB10098, PRJEB10854, PRJEB22390, PRJEB31613, and PRJEB44430, and detailed in Supplementary Table 1. The genomes of 78 modern horses, publicly available, were also accessed as indicated in their corresponding original publications, and in Supplementary Table 1.Code availability: The software to calculate generation time changes based on the recombination clock is available without restriction on Bitbucket (https://bitbucket.org/plibradosanz/generationtime/src/master/) and Zenodo (10.5281/zenodo.10842666; https://zenodo.org/records/10842666)Horses revolutionized human history with fast mobility. However, the timeline between their domestication and widespread integration as a means of transportation remains contentious. Here we assemble a large collection of 475 ancient horse genomes to assess the period when these animals were first reshaped by human agency in Eurasia. We find that reproductive control of the modern domestic lineage emerged ~2,200 BCE (Before Common Era), through close kin mating and shortened generation times. Reproductive control emerged following a severe domestication bottleneck starting no earlier than ~2,700 BCE, and coincided with a sudden expansion across Eurasia that ultimately resulted in the replacement of nearly every local horse lineage. This expansion marked the rise of widespread horse-based mobility in human history, which refutes the commonly-held narrative of large horse herds accompanying the massive migration of steppe peoples across Europe ~3,000 BCE and earlier. Finally, we detect significantly shortened generation times at Botai ~3,500 BCE, a settlement from Central Asia associated with corrals and a subsistence economy centered on horses. This supports local horse husbandry before the rise of modern domestic bloodlines.Arts and Humanities Research Council (AHRC