Annotation of the results obtained in 2018
For 2018, in order to accomplish the goals of the projpect supported by the Russian Science Foundation, research on different directions had been performd by the project participants, and thus we 1) carried out field research, indicated as the main research goal for the project which allows to obtain necessary data and 2) during the off-season carried out work associated with processing and analyses of existing and new data, including submitting field reports, preparing the results of that fieldwork for publication, and publication activity. Some results are already published in Russian and international publications (see section 1.7 for details), while others are either submitted and waiting for decision, or already accepted for publication in the next year. In total, for this particular year we have 5 works published and 3 accepted for publication in scientific journal indexed in Web of Science or Scopus listings. Articles published in 2017 and 2018 have 44 citations up to date. Current results of the project research have been presented in professional meetings. For 2018, these are 2 papers given at 2 conferences. Successful fieldwork in East Siberia in 2018 is one of the most important results. It brought extraordinary result in archaeological excavations at the Yana site, as well as in geological program in its vicinity. Field research is taking place near the Yana Paleolithic site complex in the lower reaches of the Yana site in the western Yana-Indigirka lowland, arctic East Siberia, which is one of the most remote and hard-to-access parts of Russia. For the first time, within these three field campaigns, we have systematically studied portion of the Yana B area of the Yana site’s complex, with a total of about 200 sq. meters excavated. For the first time, we have discovered a hearth within this area, with a hunting equipment workshop next to the hearth. The workshop included three production lines such as manufacture of mammoth ivory tools (points and foreshafts, or bevelled rods), production of wooden shafts with archaeological wood of about 32,000 calBP, and lithic production (manufacture of sub-triangle micro-points). The rest of the yield is typical for the Yana site elsewhere and includes a number of lithics (debitage, large side scrapers, cores) and enormous quantity of bone remains that belong to different species of the late Pleistocene fauna. Interestingly, they are different from the Northern Point area (the main excavation area of the Yana site which is fully excavated now). Thus, there are no remains of the Pleistocene hare, which is very much abundant at the Northern Point. Instead there are lots of mammoth remains that are really low at the Northern Point (about 3% within the cultural layer). Artifacts found at Yana B are also found in different composition. Thus, in this archaeological context there are no bone beads, diadems or other decorated objects, and needles are few while these find’s categories are really numerous at the Northern point. Instead, the Yana B area is reach in lithic micr-points (or pointed implements). Thus the difference between these two portions of the site is well visible while The Yana B area and the Northern Point locality are parts of the Yana site complex discovered in arctic East Siberia in 2001. Both areas belong to the same (synchronous) occupations but appear to be different in some cultural elements.This difference is evaluated by the qualitative analysis of the components found in culture-bearing strata in both site’ localities. Each component is evaluated by its physical presence in the context from zero to the presence of certain component in mass quantity. It is demonstrated that well-pronounced difference may exist within single archaeological complex that consists of synchronous parts with perfect in situ contexts. This clearly tells certain difference in human behaviour performed in diferent parts of the site and thus can be likely explained by different activity and/or seasonality of these site areas. This appears to be considered for iterpretation of the Upper Palaeolithic contexts elsewhere, specifically when constructing cultural models. This conclusion is believed to be one of the most important results of the project. In details, it is presented in Pitulko (2019, accepted ms.). It should be noted that given the extreme erosion rates in Yana river in the site area and highest information potential of this cultural resource, it is necessary to continue the work. Major conclusions on human adaptations to the late Quaternary environments are being prsented in several published or accepted articles. One of the most important of these articles is previously published regional overview of the Late Pleistocene – Early Holocene archaeological data based on the newest finds. It demonstrates the association between climatic events and settlement of the area by people, variability of human adaptations, and material culture changes (Pitulko et al. 2017). These conclusions are in line with ideas presened in work by Hoffecker, Pavlova, and Pitulko (Climate, Technology, and Glaciers: The Settlement of the Western Hemisphere, accepted ms to be published in 2019, Vestnik of Saint Petersburg University. History). The article is based on the review by Pitulko et al. (2017) and expands the research to the major problem in human prehistory is the late settlement of the Americas, which were not occupied until after 15,000 years ago from Beringia. The most likely barriers to earlier settlement are: 1) high-latitude environments (characterized by low biological productivity and extreme winter temperatures); and 2) the North American ice sheet complex, which probably blocked both coastal and interior migration routes between Beringia and NW North America at various times before 15,000 years ago. Here we argue that each was a barrier to earlier settlement, but to different human taxa. Neanderthals, Denisovans, and other non-modern representatives of Homo did not occupy latitudes above 60° North, which precluded occupation of Beringia and migration to the Western Hemisphere. The critical variables probably were: 1) resource scarcity, reflecting low plant and animal productivity; and 2) low winter temperatures. Homo sapiens, expanding out of Africa after 75,000 years ago, occupied virtually all terrestrial habitats in Eurasia no later than 32,000 years ago, including year-round settlement of the Arctic. Adaptation to high-latitude environments was achieved primarily with technologies of functional and structural complexity comparable to those of recent hunter-gatherers in similar settings. There is evidence of human settlement in Arctic Beringia before and during the Last Glacial Maximum (28,000–16,000 cal BP), and we conclude that the North American ice sheet complex is the only credible barrier to modern human occupation of the Western Hemisphere before 15,000 years ago. History of human adaptations in the early Holocene is discussed in Pitulko, Kasparov, and Pavlova “Adaptations and annual ecomonomic cycle of the oldest known hunters of the High Arctic (the early Holocene Zhokhov site, New Siberian islands)” published in 2018. Thus, at around the Pleistocene/Holocene boundary the mammoth steppe biom collapsed. For millenia, it was supporting numerous large herbivores who in turn were the endless food source for the the Pleistocene inhabitants of the Arctic regions. It was not a total crash for them but forced humans to explore new opportunities and then change their subsistence patterns. One such examples is presented by the Zhokhov site which is one of the northernmost archaeological sites in the world (76° N), indicating that the High Arctic regions had been human-populated as early as 9,000 years ago. The site yielded an enormous number of osteological remains that allow reconstructing the subsistence strategy practiced by Zhokhov inhabitants. This was a peculiar terrestrial adaptation model based on reindeer and polar bear hunting. Polar bears killed by Zhokhov hunters are adult animals and mostly medium size individuals. Typically this means females. This kind of selection can be explained only by hunting tactics when hunters were killing female bears at dens during the winter time. The Zhokhov site is found to be a base camp occupied year-round with modest summer activities, while wintertime is characterized by intense polar bear hunting. Most reindeer were hunted in the fall. Subsistence strategy of the Zhokhov hunters was largely facilitated by the fact that at the time of occupation, Zhokhov island was still part of the coastal Siberian plain margin. The local adaptation was also found to have included systematic use of sled dogs. Dogs played an important role in culture of the Zhokhov people who used the oldest known dog-sled technology. Obsidian artefacts found on Zhokhov have been provenanced using XRF analysis to allow comparison with the known sources of obsidian from north-eastern Siberia. The results indicate that the obsidian was sourced from Lake Krasnoe—approximately 1500km distant—and arrived on Zhokhov Island c. 8000 BP. The archaeological data from Zhokhov therefore indicate a super-long-distance Mesolithic exchange network, which made use of a technology for transportation highly adapted to the Arctic environment and which persisted well into historical times (see details in Pitulko et al. They come from the ends of the earth: long-distance exchange of obsidian in the early Holocene of the High Arctic, Zhokhov site, eastern Siberia (Antiquity 2019, accepted Nov. 8, 2018). Excavations on the Zhokhov Island yielded a small but meaningful collection of Early Holocene canine faunal remains. It was found that around 8,000 years ago a fully formed as a species domesticated dog was present at the Zhokhov site and used by the inhabitants of the area while hunting and as a draft animal. Presence of a developed form of dog sledding has been securely established for this culture (see Pitulko & Kasparov. Archaeological dogs from the Early Holocene Zhokhov site in the Eastern Siberian Arctic, in JASR 13 (2017), 491–515). These important questions of dog/wolf domestication (which constitutes one of the most important human adaptations and technology ever reached in human history) have further development in the examination of the Yana site materials that are probably the most important for solving this problem. To study the early stages of wolf domestication, we investigated the remains of large canids from the Yana site. Morphologically they cannot be called dogs, but there are certain indicators of the wolves’ relationship with people, favorable to the start of domestication. The sample is dominated by animals with worn, partially missing teeth and various bone pathologies. Often these animals are medium-sized. One skull of a nearly adult individual demonstrates juvenile characteristics. The morphologic and morphometric anomalies observed can be explained by commensalism (deficient and young animals using the resources of human settlement as an alternative food source). On the other hand, pathologies could have been an indirect result of commensalism, rather than its cause. Due to the risk of conflict with humans, only the most tolerant animals could live near their settlement. Experiments with living animals show, that tolerance comes at the cost of accumulating morphologic pathologies, genetically associated with tolerance, which was observed in many Yana wolves. Thus we conclude that high sociality and vocal behavior allowed wolves to approach human settlements, becoming some of the earliest domesticated animals. The site yielded evidence of a special attitude towards wolves, perhaps indicating a totemic cult. The Yana site material, interpreted in light of the biological characteristics of wolves, demonstrates for the first time the earliest stages of domestication, which can be characterized as self-domestication (see Nikolskiy et al. Predomestication wolf-human relationships in the northern East Siberia of 30 000 years ago – evidence from the Yana Paleolithic site, arctic Siberia. Stratum plus 1 (2018), 231-262). During the fieldwork in Yana, we have collected a long-term row of observations on the river side erosion developing in the Yana site area. These data are in line with observations done in different Arctic regions. They are put together in Hollesen et al 2018 (Climate change and the deterioration of the Arctic’s archaeological and environmental archives, in Antiquity 92 (2018), 574–587). It is concluded that the cold, wet climate of the Arctic has led to the extraordinary preservation of archaeological sites and materials that offer important contributions to the understanding of our common cultural and ecological history. This potential, however, is quickly disappearing due to climaterelated variables, including the intensification of permafrost thaw and coastal erosion, which are damaging and destroying a wide range of cultural and environmental archives around the Arctic. In providing an overview of the most important effects of climate change in this region and on archaeological sites, the authors propose the next generation of research and response strategies, and suggest how to capitalise on existing successful connections among research communities and between researchers and the public. We believe these conclusions to be important for future economic and cultural development of the Arctic regions. There are additional important findings including genetics (wolf and horse) to be found in Leathlobhair et al., The Evolutionary History of Dogs in the Americas, in Science 361, 81-85 (2018), Gaunitz et al. Ancient genomes reveal the ancestry of modern domestic horses and the feral origins of Przewalski’s horses. Science 360, 111-114 (2018), Stronen et al. Genomic variability in the extinct steppe bison (Bison priscus) compared to the European bison (Bison bonasus), in Mammal Research (2018, on-line first publication). Finally, we should mention prepared maniscript under consideration by Sikora M., Pitulko V.V., Sousa V.C. et al. 2018. Ancient genomics reveals three prehistoric migrations into northeastern Siberia and the genetic origins of Native Americans (reference number: 2018-02-02616).

 

Publications

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Annotation of the results obtained in 2016
To accomplish the project goals (see 1.2) in 2016 we conducted the following with the support of RNF: (1) fieldwork which was established as the main project goal in 2016 and (2) labwork related to analyzing existing and newly collected data. Project work carried out in 2016 focused on the Yana site complex and its vicinity to obtain comprehensive information about the most ancient inhabitants of the Siberian Arctic and the environment they occupied. In 2016 we carried out an expedition with nine people who studied the distribution and structure of various Quaternary sediments, the region’s geomorphology and geocryology, in addition to collecting faunal material. In the profiles of second and third terraces, we continued collecting samples for palynological analyses, microtheriofauna samples, fossil insects, and ancient ice samples for analysis of isotopic oxygen and hydrogen composition. Put together, these data allow reconstructing the paleogeographic conditions occupied by humans and the history of environmental development of the area surrounding the site. During the 2016 investigations we sampled three profiles of quaternary sediments and collected 59 ice samples and 37 radiocarbon samples. This season was characterized by remarkably high rate of riverbank erosion. It is clear from our observations that the entire area of the Yana site excavated over the previous years, including all unique data and exclusive artifacts could be lost within one season. It is thus imperative to continue investigating here. Archaeological work took place at the Yana site and around it to study geology and stratigraphy of the site, as well as studying the artifact-bearing parts of locales Northern and Yana-B. The Yana-B locale was not accessible because mammoth ivory collectors washed the bank away, forming a sheer frozen bluff. The same circumstances delayed our work in the Upper locale, where we are studying a redeposited artifact-bearing horizon. This material is approximately 40,000 years old. By now, we have tested 16 locales, each has been described, sampled for pollen analyses and radiocarbon dating, and where necessary, ice was sampled from ice lenses. At the Northern locale, we studied a cultural level remnant, preserved in 2015 (15 m2 excavated), and a portion of the cultural level, which landed on the beach as part of a large frozen block of the shore. This block contained a relatively small (25 m2) but rich part of the cultural level and contained a hearth. In addition, we surveyed fresh frozen bluffs, creating maps of artifacts found and profile elements. In the frozen wall of a newly formed river bluff we found a “cache” of longitudinally split medium-sized mammoth tusks (preforms, cached by the site inhabitants in a low point, in a wet/swampy area near the dwellings). The cultural level remnant found on the beach, was severely damaged in the fall: it consists of three parts which remained in place after the block fell down. One of these contained the hearth. We found rich material in these chunks, including many objects of a hunting toolkit (points and foreshafts made from mammoth ivory, mostly broken and poorly preserved), beads, pendants made from teeth, needles, many lithic artifacts, including microtools (tools made on flakes) of standard size and shape. We should note the discovery of a “cache” of such tools near the hearth. Excavations in the Yana-V locale were mostly preliminary and included removing the overburden, establishing a drainage system, and cleaning of artifacts and features in the exposed cultural level along the edge of the polygon. Such spatial distribution of material is characteristic of the Yana site (and other archaeological sites, where the cultural horizons are buried in the permafrost deposits with syncryogenic freezing). In total we excavated 35 m2 here in 2016; collected material includes micro-points and other microtools. There are also ivory foreshaft and point fragments, as well as needles. Similarly to the Northern locale, this material is accompanied by flakes and implements from quartz crystal, including micro-points with a dulled edge. In the faunal collection from this area, we see mostly bison remains; also present are bones of medium-sized mammoths and fragment of large bones of these animals with evidence of intentional fracture of these bones by people to obtain bone marrow and to prepare the bones for use as fuel for fires. This behavior was not observed previously. During the off season, we worked with the results of pollen, paleoentomological, paleocarpological (Ye.Yu. Pavlova, Ye.V. Zinovyev, along with О.M. Corona), and radiocarbon analyses. In the radiocarbon lab of the IIMK RAN, S.S. Rishko obtained 37 new dates from Pleistocene faunal remains from our collections, peat and wood samples from the profiles in the Yana site region (samples collected and prepared by Ye.Yu. Pavlova, V.V. Pitulko). Information regarding archaeological objects (except those from 2016) was added to the database for the Northern locale of the Yana site (the 2016 materials are currently being processed by A.A. Bessudnov, A.V. Larionova, K.N. Stepanova. Ye.S. Tkach, and V.V. Pitulko). The results of this work will be useful at the next stage of site material analysis. In 2016, a lot of work was done with the faunal collection. Faunal remains from the archaeological collection and assemblages (32,016 whole bones and bone fragments) have been identified; from canine (craniofacial area) and human (primary teeth) bone remains, obtained from the Yana site excavations, we selected samples for fossil DNA studies. Morphological and morphometric research of canine remains from the Yana site, in comparison with recent and ancient canine finds of various ages from the Yana site surroundings, has shown that: (1) all canine remains from cultural levels are confidently diagnosed as those of Canis lupus L. (grey wolf). They do not differ from the many fossil and recent wolf remains from the Yana site surroundings and have no morphological and/or morphometric characteristics that would indicate a close relation to dogs; and (2) the remains of a chronologically younger (about 880 14C yrs.) canine from the sediments above the cultural layer, are confidently determined to be Canis familiaris L. (dog). Thus, morphological and morphometric studies of canine bone remains from the Yana site exposed no signs of wolves being deliberately selected by ancient people in the area during the timeframe investigated. Simultaneously, the established ritual use of wolves shows that the wolf had been distinguished by the man from other mammals, which may indicate the earliest stage of wolf domestication in North Asia. Mammoth bone remains (scapulae and ribs) from the Yana site excavations have been preliminarily studied to expose hunting behavior and/or butchering marks. A total of about 500 separate bones have been studied, exposing a series of scapulae and ribs injured by hunting or other impacts. Such injuries have been preliminarily described and topologically analyzed; each such object has been provided with detailed individual description (item ID) (V.V. Pitulko, P.A. Nikolsky). The collection of bison radiocarbon dates has been tentatively estimated to discover time-space dynamics of the species that served as an important subsistence resource for ancient humans (P.A. Nikolsky, V.V. Pitulko). The relative numbers of West Beringian bison, which we reconstructed using time density of radiocarbon dates, varied significantly over the past 50,000 years. The general trend of these changes basically follows the Milankovich curve, i.e. depends directly on global temperature changes. However, bison numbers changes on a smaller scale expose some interesting pattern, especially in comparison with changes in the number of mammoths in the area of research. Both the bison and the mammoth reached their maximum numbers (within the timeframe available for radiocarbon dating) 34,000-38,000 years ago. Later their numbers decreased, fluctuating cyclically. Such fluctuations of the mammoth number most closely followed the changes in the population of xerophyte beetles in entomofaunas, which, in turn, is the marker of steppe vegetation in West Beringia’s Pleistocene phytocenoses. Fluctuations of the number of bison after 34,000 years ago were opposite to the fluctuations of the number of mammoths. Opposite changes in numbers of mammoths and bison might have resulted from the species’ competition for resources (steppe vegetation) which lead to mutual population regulation. Apparently, for a long while (at least for 20,000 years, between ~30,000 and 9,500 years ago), the bison successfully coexisted with human in West Beringia. In the faunal materials from the Yana site, bison remains dominate significantly. However, human presence might have been fatal for the bison around 9,500 14C years ago, at the same time and in the same way as for the mammoth: it was a period of significant decrease in their number and habitat, resulting from the environmental change in early Holocene. Both species were essential for ancient human populations in Arctic Siberia. We reconstructed the Late Neopleistocene-Holocene environment and the conditions of the initial peopling of the Yana-Indigirka Lowland. The work involved radiocarbon dates obtained by the Institute of Material Culture History (RAS), Geological institute (RAS), andvBeta Analytic Inc. (Miami, Florida, USA). For paleoclimatic reconstructions we used palinological analysis results, represented by 9 pollen diagrams that characterize the whole profile of the Yana site. In total, 194 samples have been analyzed. The diagrams are characterized by 46 radiocarbon dates. Additionally, we used the data from the analysis of vegetative macroremains obtained from four section fragments, where 26 samples have been analyzed and 23 taxa were distinguished. Carpological and entomological research has been completed for one vertical profile, from which 18 samples have been selected and analyzed. During the carpological analysis, 15,665 macroremains (86 taxa) were selected; those were vegetative and generative remains of plants and their fragments. In the course of the entomological analysis, over 10,000 remains were extracted and 7,656 insect fragments were assembled and identified. Paleoclimatic reconstructions for the second half of Late Neopleistocene-Holocene were created based on the analysis of a set of paleofloral data (from palinological analysis and the analysis of vegetation macroremains) from the section of Quaternary deposits in the area of the Northern excavation locale of the Yana site, accompanied by reliable radiocarbon (14C) dates. The basis for the paleoclimatic reconstruction methodology is the methodology of reconstructing climatic indicators from floral materials developed by V.P. Grichuk (1969). The originality of the approach used for paleoclimatic reconstructions is the opportunity to distinguish, within the studied sections of Quaternary deposits, chronological levels with the interval of 500-1000 years, characterized by paleofloral materials. Using the method of calculating climatic indicators we were able to obtain a virtually continuous record of climatic changes over the period 37,000-10,000 yrs. B.P. For the first time, we obtained high-resolution records of climatic changes (with the resolution of 500-1,000 years) for the Yana-Indigirka Lowland, represented by graphs of averaged maximum and minimum deviations from the present indicators of the temperature of the warmest month, the average annual temperature, and the average annual precipitation. By using the suggested methods of material processing we not only exposed the basic trend of paleoclimatic changes in the second half of Late Neopleistocene, but also researched the succession of climate fluctuations within the Kargin (Late Wisconsin) megainterval (MIS3), the Sartan stadial (MIS2), and the end of the Holocene (MIS1), determined the timing and intensity of the maximum cooling during the Sartan cryochrone, clarified the chronological transition to Holocene for the Yana-Indigirka Lowland, and formed a quantitative paleoclimatic assessment of this transition. Palynological data became the basis for a detailed description of landscape changes during the second half of Late Pleistocene – Early Holocene, supported by carpological and entomological analyses. Environmental conditions both during MIS 3 and MIS 2 influenced the fate of the inhabitants of these areas and were mild enough to allow people to spread into and live in the Siberian Arctic. The results of our investigations show that the question regarding the LGM depopulation of Siberia can be closed. This is the most important result of the year of project investigations reported here.

 

Publications

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Annotation of the results obtained in 2017
To accomplish the goals of the projpect (see section 1.2) in 2017 we (with support from the RSF) 1) carried out field research, indicated as the main research goal in 2017 and 2) during the off-season carried out work associated with processing and analyses of existing and new data, including submitting a report on the 2016 fieldwork to the Division of Field Research (Institute of Archaeology, Russian Academy of Science) and preparing the results of that fieldwork for publication). Some results were published in Russian and international publications (see section. 1.7), the most important of these articles is the regional overview of the Late Pleistocene – Early Holocene archaeological data, which demonstrates the association between climatic events and settlement of the area by people, variability of human adaptations, and material culture changes (Pitulko V., Pavlova E., Nikolskiy P. Revising the archaeological record of the Upper Pleistocene Arctic Siberia: Human dispersal and adaptations in MIS 3 and 2. Quaternary Science Reviews Vol. 165 (2017) P. 127-148). In another important research manuscript, focused on the question of wolf/dog domestication, we examined the oldest in Siberia mass collection of Early Holocene dog remains from the Zhokhov Island excavations. In this article, (Pitulko V.V., Kasparov A.K. Archaeological dogs from the Early Holocene Zhokhov site in the Eastern Siberian Arctic. Journal of Archaeological Science: Reports. Vol. 13 (2017) P. 491–515), based on the study of a large amount of comparative material, we determined main diagnostic characteristics which allow clearly differentiating between dogs and wolves, and articulated some useful considerations regarding the evolution of these animals. This work aroused great interest from the research community, including in the Science journal (http://www.sciencemag.org/news/2017/05/earliest-evidence-dog-breeding-found-remote-siberian-island), as an important research finding of break-through level. Current results of the project research have been presented in national and international conferences: in total, project participants presented 17 reports at nine scientific meetings (more details in section 1.10). Field research is taking place near the objects of the Yana Paleolithic site in the lower reaches of the Yana site (west Yana-Indigirka lowland, Arctic East Siberia). The main goal of this fieldwork is studying a new part of the site – Yana-B area, which was previously only tested on a few occasions (in 2003-2009, 2014 and 2015). In total 30 sq. m. were excavated. We determined, that this part of the site is characterized by thick ash concentrations, full of burned bones. In addition, it has large numbers of bones from various animals. Faunal composition of the Yana-B area is considerably different from the Northern area, with many remains of mammoth (mainly smaller individuals and/or juveniles), noticeable presence of rhinoceros, among other herbivore species, it appears, horse dominates, while the portion of reindeer is lower. The artifact collection demonstrates the waste from manufacture of various implements from mammoth tusk, including a considerable number of hunting complex items: long massive points and foreshafts, represented in fragments. Also characteristic are serial micro-tip forms. They were used to equip the tips of the Yana hunters’ main hunting implements. From the collections in fresh exposures between the Yana-B and Northern points, the Yana-B area itself, and from the Yana mass accumulation of mammoth (YMAM), we obtained a new collection of mammoth, bison, and horse faunal remains with characteristic traces of hunting impact: holes, traces of stabbing and cutting penetrating wounds, remnants of hunting implements, stuck in the animals’ bones during a hunting episode. This collection exceeds all evidence of this kind in the world; it is a unique and larges collection in the world, and we continue preparing it for publication. While working at the Yana site, we determined that in 2016-2017 the rate of river bank erosion was so high, that deposits on the left bank of the Yana river were significantly damaged in the area from Yana-B to the Northern sector and further downstream. The rate of brow retreat was measured instrumentally, indicating that in 2017 it was significantly higher than the average value (around 6m), and in some areas was at least 15m/year. This underlines the need to continue excavations in 2018. We continued studying the geology of the Yana site region. For example, we for the first time determined the presence of bedding with sediments identical to those from the Quaternary exposures higher upstream. We were able to collect samples from the lower portions of exposure on the second Yana River terrace above the floodplain for radiocarbon, palynologic, paleoentomologic and paleobotanic analysis. Similar work took place in the basal levels of the exposure on the third terrace above the floodplain (at the bottom of the exposure, which was previously not accessible), where we also made important observations, which clarify the geological composition of this formation. In total, 12 profiles of various length were investigated and samples were collected for various analyses. Important paleontological finds were discovered during the fieldwork, which will be useful for developing the biostratigraphic method. For example, in the lower portion of the exposure on the third above-floodplain terrace we found an in situ fossil moose antler Cervalces sp. (archaic species, transitional between Cervalces gallicus and Cervalces latifrons). Such finds are very rare: in Siberia only two other samples are known, and unlike our sample, they come from collections. This find is key to understanding moose evolution and, respectively, becomes an important biostratigraphic benchmark. During the off-season, we continued working with the results from palynologic, paleoentomologic, and carpological analyses. We developed and tested the main scheme for carrying out paleogeographic reconstruction based on paleofloristic data. While implementing the developed scheme of paleogeographic investigations, we built models of precipitation for several segments of the second Yana River terrace exposure in the vicinity of the Northern point of the Yana site. This allowed us to correctly separate them chronologically, with a 500-1000-year interval, to avoid distortions caused by different velocities of sedimentation and cryogenic deformations of the deposit horizons in the section, to define hypsometric positions of sediments formed simultaneously in different parts of the section. Based on systematic composition, structure, and component ratio in palinospectra as well their comparison with the recent spectra parameters, vegetation reconstruction has been performed for certain time slices within the 37-10 K 14C yr. interval. Results of vegetation reconstructions are presented as collective diagrams of spore-pollen spectra and integrated compositions of fossil vegetative communities, reflecting the dynamics of vegetation development from tundra-steppe MIS 3 phytocenoses to tundra communities of the Early Holocene. Selected species definitions of pollen, spores, and vegetative macroresidues of fossil phytocenoses for each chronological section within 37-10 K 14C yrs. served as material for quantitative paleoclimatic reconstructions of air temperatures in the warmest month (twstm, ºС), mean annual air temperature (tm.an, ºС), and mean annual precipitation (Pm.an, mm/yr.), performed using climatograph summing and arealographs. Results of paleoclimatic reconstructions are presented as a table and graphs of mean minimal and mean maximal deviations from the modern parameters of air temperature in the warmest month (min Δtwstm, max Δtwstm), mean annual temperature (min Δtm.an, max Δtm.an), and annual precipitation (min ΔРm.an, max ΔРm.an), which comprehensively limit the range of possible values for reconstructed climatic characteristics. Implementing the principal scheme of basing paleogeographic reconstructions on paleofloristic data, we managed to specify the previously revealed course of landscape and climate changes for the Yana-Indigirka Lowland in Late Neopleistocene and to essentially itemize the previously performed reconstructions for the Late Glaciation – turn of Holocene. Complex data from the carpological and entomological analyses, as well as from the analysis of humus from deposits of the section of the second Yana River terrace near the Northern Point of the Yana Site reflect bioclimatic changes during the formation of the sediment mass within the 37-10 K 14C yr. interval. Samples, taken directly from the cultural layer at the Northern Point of the Yana Site and analyzed carpologically and entomologically, showed that at that time vegetation had been represented by various ecologic groups, reflecting the existence of mosaic landscapes, where variously swamped tundra communities neighbored cryophyte-steppe and vegetative communities of sod-free substrates. Domination by the most xerophilous beetle species and poor species composition of the entomofauna from the site cultural layer reflect the wide development of open sand spots covered with xeromorphous vegetation. Humus content and fraction-group composition showed that the cultural layer had been formed in the lower microbiological activity of soils. The analysis of paleoentomological and carpological records from different parts of the second terrace of the Yana River (sections LY/EF and LY/SS) has showed that the exposed differences in compositions of simultaneous entomocomplexes and phytocenoses in samples from the lower part of Cut LY/SS, demonstrating distribution of meadow vegetation, are associated with peculiarities of local habitats that existed there about 27.5 K 14С yrs. BP. In both cases, deposits were formed in a cold and relatively dry climate, widely developed were open landscapes similar to today’s typical tundras with conspicuous participation of cryophyte-steppe communities and vegetative communities of sod-free substrates. The vegetative macroresidues composition changing up the section indicated the humidity decrease after 27 K 14С yrs. BP, accompanied by a gradual change of vegetative communities. The species composition of the modern Coleoptera is most similar to the entomologic complexes of the Early Holocene from the LY-EF2 exposure, which indicates that during that time forest-tundra landscapes, similar to the modern environments, existed there. The results of the complex investigations of the Yana site Quaternary deposits using the carpological, entomologic, and humus analysis correlates well with the results of paleogeographic reconstructions, created based on the palynological investigations, which increases the reliability of reconstructions. The results of our paleogeographic reconstruction yielded not only an environmental characteristic of the conditions surrounding the appearance of people in the west Yana-Indigirka lowland near the Yana site 28,500-27,000 14С years ago during the Karga thermochron (MIS 3), but also reconstructing the paleoclimate of periods, during which the presence of people is clearly established in north and east Yana-Indigirka lowland during the Sartan chryochron and the LGM (MIS 2). Based on the complex analysis of the paleoclimatic reconstructions and climatic data from over 5,000 weather stations from across former USSR, we constructed maps of current geographic locations, characterized by similar climatic conditions to those, experienced by people living on the Yana-Indigirka lowland during certain time periods. These maps visually demonstrate that people could establish themselves in this area during the late Neopleistocene, including the Sartan cryochron. Brief information regarding project completion can be found at the web-site of the Institute of History and Material Culture: http://www.archeo.ru/struktura-1/otdel-arheologii-paleolita/nauchnye-proekty-otdela-arheologii-paleolita/proekt-n-16-18-10265-rnf/

 

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