The transitions from foraging to farming and later to pastoralism in Stone Age Eurasia (c. 11-3 thousand years before present, BP) represent some of the most dramatic lifestyle changes in human evolution. We sequenced 317 genomes of primarily Mesolithic and Neolithic individuals from across Eurasia combined with radiocarbon dates, stable isotope data, and pollen records. Genome imputation and co-analysis with previously published shotgun sequencing data resulted in >1600 complete ancient genome sequences offering fine-grained resolution into the Stone Age populations. We observe that: 1) Hunter-gatherer groups were more genetically diverse than previously known, and deeply divergent between western and eastern Eurasia. 2) We identify hitherto genetically undescribed hunter-gatherers from the Middle Don region that contributed ancestry to the later Yamnaya steppe pastoralists; 3) The genetic impact of the Neolithic transition was highly distinct, east and west of a boundary zone extending from the Black Sea to the Baltic. Large-scale shifts in genetic ancestry occurred to the west of this "Great Divide", including an almost complete replacement of hunter-gatherers in Denmark, while no substantial ancestry shifts took place during the same period to the east. This difference is also reflected in genetic relatedness within the populations, decreasing substantially in the west but not in the east where it remained high until c. 4,000 BP; 4) The second major genetic transformation around 5,000 BP happened at a much faster pace with Steppe-related ancestry reaching most parts of Europe within 1,000-years. Local Neolithic farmers admixed with incoming pastoralists in eastern, western, and southern Europe whereas Scandinavia experienced another near-complete population replacement. Similar dramatic turnover-patterns are evident in western Siberia; 5) Extensive regional differences in the ancestry components involved in these early events remain visible to this day, even within countries. Neolithic farmer ancestry is highest in southern and eastern England while Steppe-related ancestry is highest in the Celtic populations of Scotland, Wales, and Cornwall (this research has been conducted using the UK Biobank resource); 6) Shifts in diet, lifestyle and environment introduced new selection pressures involving at least 21 genomic regions. Most such variants were not universally selected across populations but were only advantageous in particular ancestral backgrounds. Contrary to previous claims, we find that selection on the FADS regions, associated with fatty acid metabolism, began before the Neolithisation of Europe. Similarly, the lactase persistence allele started increasing in frequency before the expansion of Steppe-related groups into Europe and has continued to increase up to the present. Along the genetic cline separating Mesolithic hunter-gatherers from Neolithic farmers, we find significant correlations with trait associations related to skin disorders, diet and lifestyle and mental health status, suggesting marked phenotypic differences between these groups with very different lifestyles. This work provides new insights into major transformations in recent human evolution, elucidating the complex interplay between selection and admixture that shaped patterns of genetic variation in modern populations.

There are two competing hypotheses for the origin of megaliths in Europe. The conventional view from the late 19th and early 20th centuries was of a single-source diffusion of megaliths in Europe from the Near East through the Mediterranean and along the Atlantic coast. Following early radiocarbon dating in the 1970s, an alternative hypothesis arose of regional independent developments in Europe. This model has dominated megalith research until today. We applied a Bayesian statistical approach to 2,410 currently available radiocarbon results from megalithic, partly premegalithic, and contemporaneous nonmegalithic contexts in Europe to resolve this long-standing debate. The radiocarbon results suggest that megalithic graves emerged within a brief time interval of 200 y to 300 y in the second half of the fifth millennium calibrated years BC in northwest France, the Mediterranean, and the Atlantic coast of Iberia. We found decisive support for the spread of megaliths along the sea route in three main phases. Thus, a maritime diffusion model is the most likely explanation of their expansion.

ABSTRACT. Approximately 2700 radiocarbon results are currently available from European megalithic contexts. The interpretation of these 14 C dates is often difficult. It is not easy to connect many of them from their archaeological context to the construction or the burial phase of the graves. This paper focuses on the megaliths of Scandinavia-a special megalith region-as it is the only place in Europe with 14 C dates directly referable to the construction of the passage graves, the graves have good bone preservation, and new dating sequences are available. Some 188 14 C results are now available from Scandinavian passage graves. In Sweden, new data suggest that these graves were built from the first half of the 35th century BC onwards. The 14 C dates from birch bark as filling material between dry walls make it possible to build a sequence for the construction phase of the passage graves in Denmark from the 33rd century BC onward. With an interpretative Bayesian statistical framework, it is possible to untangle the nuances of the differences for the origin and the spreading of the megaliths in the different regions, to define, together with the archaeological remains, possible cultural-historical processes behind these phenomena and to discuss diffusion versus convergence.

The history of research on the Neolithic of the Atlantic façade shows how speculation about prehistoric mobility, especially across the sea, is mainly based on three types of archaeological evidence: megalithic monuments, rare stones, and pottery decoration. With the aim of approaching the issue from other perspectives, we have focused on the Morbihan area, a focal point of the European Neolithic during the mid-5th millennium BC. The analysis of this area has allowed us to grasp which objects, ideas and beliefs may have been desired, adopted and imitated at the time. We shall begin with an architectural concept, the standing stone. These were sometimes engraved with signs that can be directly compared between Brittany, Galicia (NW Spain) and Portugal, but for which there are no intermediate parallels in other areas of the French or Spanish coast. The unique accumulation and transformation of polished blades made of Alpine rocks and found inside tombs or in other sort of depositions in the Carnac region allowed us to establish a second link with Galicia and the Atlantic coast of the Iberian Peninsula, where certain types of the axes were imitated using a set of different rocks (sillimanite, amphibolite). Finally, the variscites and turquoises from different Spanish regions were used for the manufacture of beads and pendants at the Carnacean tombs, without it being possible – once again – to retrieve similar objects in the intermediate areas. The mastery ofdirect Atlantic sea routes is posed as an explanation for this geographical distribution. But, beyond the information drawn from specific artefacts – whose presence/absence should not be used in excess as an argument to endorse or underrate such movements across the ocean – we will return to a more poetic and universal phenomenon: the spell of the sea. Therefore, we will focus on the depictions of boats on the stelae of Morbihan to open such a debate.