Eliza Stolarczyk

Salmonella enterica subsp. enterica is an extremely diverse bacterial pathogen causing frequent infections and foodborne disease among human populations. More than 1500 different bacterial strains (serovars) have been described, many with a wide host range. A small number of serovars are adapted to infect specific hosts: of these, serovars Typhi and Paratyphi A, B, and C cause primate-specific systemic infections (typhoid and paratyphoid fever). Although Paratyphi C is one of the rarest human-specific serovars today, it was once widespread, and all ancient Salmonella genomes published to date belong to or are ancestral to this lineage. Here, we present 53 new ancient Salmonella genomes spanning Eurasia and dating between 3500 BCE and 1300 CE. This rich genomic dataset allows us to reconstruct the evolutionary history of this pathogen in unprecedented detail. We identify multiple extinct prehistoric lineages that caused infections throughout Eurasia. Multiple lineage replacement events are observed throughout prehistoric and historic times, and Bayesian phylogenetic analysis is used to date and identify host adaptation events within this lineage. We find that host-adapted sublineages Paratyphi C, Choleraesuis, and Typhisuis continued to evolve host specificity independently from each other. We reconstruct signals of convergent host adaptation in the studied lineages and other host-adapted strains by analysing shared pseudogenes and recurrent gene gain and loss events. This analysis demonstrates a role for host interactions as a particular target of selection, highlighting the gradual adaptation of this S. enterica lineage to humans that coincides with the intensification of animal husbandry in pastoralist and sedentary farming societies.

When findings of radiocarbon dating differ from method to method, researchers deal with this issue in absolutely different ways. This study is a case that compares two dating series of one Late Bronze kurgan. This kurgan is one of the Srubnaya-Alakul antiquities in the South Transurals. Even though the researched material is the same (human bone collagen), the scope of findings is comparable (19 LSC dates and 29 AMS dates) and the same individuals (n = 14) were dated repeatedly, the differences are still significant. In addition, every series in particular does not show any signs of static emissions. Bayesian modelling of the monocultural kurgan chronology (single-phase model) allows to determine boundaries of the intervals and assess durations for each series. LSC series covers the period between 20th and the mid-18th century BC (up to 167 years long), while AMS series covers the period between the mid-19th and the early 17th century BC (up to 34 years long). Most cases showed statistically different dates for the same individuals studied with different technologies. AMS version of the kurgan chronology conforms better to the previously determined parameters of the Alakul culture. The kurgan’s short chronology is also confirmed by only three generations of kin determined through DNA tests. It means this part of the necropolis could not function too long. Before we reveal the reasons of systematic discrepancies in different date series, it is not practical to consolidate them as it would affect reliability of conclusions both in the general chronology of the archaeological culture and in recovering the ‘history of life’ for a particular site.

Our understanding of prehistoric societal organization at the family level is still limited. Here, we generated genome data from 32 individuals from an approximately 3,800-y-old burial mound attributed to the Bronze Age Srubnaya-Alakul cultural tradition at the site of Nepluyevsky, located in the Southern Ural region of Central Eurasia. We found that life expectancy was generally very low, with adult males living on average 8 y longer than females. A total of 35 first-degree, 40 second-degree, and 48 third-degree biological relationships connected 23 of the studied individuals, allowing us to propose a family tree spanning three generations with six brothers at its center. The oldest of these brothers had eight children with two women and the most children overall, whereas the other relationships were monogamous. Notably, related female children above the age of five were completely absent from the site, and adult females were more genetically diverse than males. These results suggest that biological relationships between male siblings played a structural role in society and that descent group membership was based on patrilineality. Women originated from a larger mating network and moved to join the men, with whom they were buried. Finally, the oldest brother likely held a higher social position, which was expressed in terms of fertility.

The article presents preliminary results of the study of the Bronze Age settlement Konoplyanka 2 in the valley of the Karagaily-Ayat River (Kartaly district of the Chelyabinsk region). The materials demonstrate the manifestations of mobility that occurred in different chronological periods of the Late Bronze Age. Topical problems such as the existence of open villages in the South Trans-Urals in Sintashta time and the features of post-Sintashta age settlements are also investigated. The settlement consists of clusters formed by close or adjacent buildings with a linear planning principle. Line 1 consists of the rectangular structures of the Srubnaya (first phase) and Cherkaskul (second phase) cultures. Four wells located along the central axis were discovered in the excavated building. Line 2, with no external features, was discovered by geophysical studies. The building under study contained the Abashevo type ceramics and traces of metallurgy typical for the Sintashta and Abashevo cultures. Radiocarbon dates span an almost continuous interval from the 20th to the 16th century BC, in which the Abashevo claster occupies the earliest position, being partially synchronous with the earlier investigated fortified settlement of Konoplyanka, but not culturally related. The cluster of the Srubnaya-Cherkaskul houses is the latest. The article discusses the diachronic settling and issue of the eastwards spread of the Abashevo population, and the assimilation of the Trans-Urals by Srubnaya cultural complex population.

This article introduces a series of AMS radiocarbon dates for the Bronze Age Petrovka cemeteries in the Trans-Urals. The results of the AMS¹⁴C-dating of animal and human bones indicate a very high degree of concordance in the 19th and 18th centuries cal BC time range. The previously obtained AMS datings clearly fi t into the same chronological interval. Specifi cally, 17 of 36 analyses of the Petrovka series yielded very similar results. In other cases, where dating was based on wood and charcoal, the results are highly inconsistent, even within the same burial. Before the verifi cation of these results, the short interval based on AMS dates should be preferred. Its comparison with intervals for other cultures of the Trans-Urals demonstrates marked similarity: in fact, complete coincidence of some of them. At the same time, stratigraphic and typological evidence suggests that the Sintashta, Petrovka, and Alakul traditions are stages of a sequence. Additional arguments are features of continuity in the material culture and the practice of using the burial mounds of a previous culture for new graves, without destroying the older ones. In our view, the only explanation is provided by a dynamic scenario of cultural change spanning two centuries, from the migration of the Sintashta people to Southern Urals until the formation of the Alakul culture. The resolution of the radiocarbon method does not suffi ce to detect such rapid changes. If this explanation is correct, the Petrovka sites should be considered an early stage of the Alakul culture, rather than a separate culture.

Краузе Р ., Епимахов Рђ.Р’., РљСѓРїСЂРёСЏРЅРѕРІР° Р•.Р’., РќРѕРІРёРєРѕРІ Р