Gennady Gavrilovich Boeskorov

The fur of the mummy of an adult female brown bear (Ursus arctos) (3500-year old ‘Etherican bear’, Holocene) found in Yakutia was studied using light and scanning electron microscopy. It was compared to the fur of recent bears, showing their similarity in color, differentiation, and hair fine structure. The fur forms a coarse, tangled, and springy pelage due to polymorphism and size and dimensional characteristics of guard hairs (length and thickness, degree of development of the medulla, height and patterns of the cuticle), and wavy profile of the hair shaft. This cover effectively protects the animalꞌs body from mechanic damage due to damping and preventing skin over-hydration. The air-bearing medulla of the hairs is poorly developed, which, together with the absence of a thick underfur, reduces the heat-protective properties of the fur, which is compensated for by a significant air layer in the loose, shaggy fur made of chaotically intertwined wavy hairs.

The steppe bison (Bison priscus Boj.) was one of the most widespread and abundant large mammals of the Pleistocene Mammoth fauna across Eurasia. Until recently, it was generally assumed that this species had vanished from this region at the end of the Pleistocene. This article analyzes archaeological data on finds of bison remains in the Holocene, together with the results of new radiocarbon dating obtained from the latest finds. These data indicate that the steppe bison persisted well into the Holocene. During the early Holocene (Preboreal and Boreal, 10,200–8,000 years BP), bison remains are recorded from numerous localities in northern Western Europe, with sporadic records extending across the northern Russian Plain, the upper Ob River basin inWestern Siberia, and further east into Siberia and North east Asia. However, their numbers were apparently already low. For the middle and late Holocene of Eastern Europe, a few dated bison remains (most likely of the wisent, Bison bonasus (L.)) have been found from the southern Baltic coast and the Volga River basin on the Central Russian Upland. In Eastern Siberia, mid-Holocene (Atlantic period, 8,000–4,600 yr BP) finds are confined to the Lake Baikal region. The discovery of Subboreal-age bison bones (3,000 yr BP) from the Ust-Tokko site and possibly from Malaya Munku site, together with zoomorphic depictions at the Suruktaakh-Khaya locality, suggests that one of the last refugia of the steppe bison was located in the basins of the Tokko and Olekma rivers (southwestern Yakutia).

This study reports on the first Mustelidae find from the Arctic (NE Yakutia) sealed in intact Pleistocene cryolithic beds. A morphological analysis of semi-adult male sable remains—cranium and dentalia—shows a close affinity with the modern subspecies Martes zibellina jenisseensis . Absence of damage and attrition of the bone surface indicate in-situ burial of the ancient cadaver prior to soft-tissue decomposition. Just minor signs of microbial decay and post-mortem diagenesis changes in the osteological structure of the well-preserved skull and maxilla are consistent with long-term deep freezing. This fossil sable from the Ogorokha site (Central Indigirka, 68°23'N) is ¹⁴ C-dated to > 45,000 BP, i.e., it is older than ~47,000 calendar years. The modern analogue of this typical woodland animal occupies today open taiga habitats in southern Siberia. The fossil sable shows that climatically moderate circumpolar interstadial ecosystems are conserved in local yedoma deposits. This unique find indicates a former geographic distribution of sable far north into the present sub-arctic and arctic territories, and supports the existence of biotically rich forest refugia during the Last Glacial.

Water fleas of the family Moinidae Goulden, 1968 (Crustacea: Cladocera) inhabit ephemeral and permanent water bodies. Like other cladocerans, dormant stages of moinids, namely ephippia (modified molt exuvia) containing resting eggs, play a crucial role for their survival and dispersal. However, in contrast to Daphniidae, moinid ephippia are poorly investigated. In this study based on original and previously published data, we summarize information on the ephippia of the genus Moina Baird, 1850 and discuss their value as a source of information for paleoecological reconstructions. In toto, we analyzed more than 140 ephippia and gamogenetic females of recent and fossil populations from different zoogeographical zones and provide descriptions and illustrations for all revealed types of ephippia, as well as brief comments on taxonomy, ecology and distribution of species and species groups to which they were belonged. Our data on the morphological diversity of moinid ephippia cover only a part of the taxa currently described. However, our brief study revealed a remarkably high diversity of ephippial ornamentation patterns relative to other families of Cladocera. Some patterns of ephippial ornamentation are widely distributed and could be found in different zoogeographical zones. Other types seem to have more local distribution. Based on our observations, the structure of ephippia may be valuable for a preliminary brief identification of species groups, especially small-sized micrura-like taxa. Species with peculiar ephippia also were found, but after closer examination, they may represent groups of sibling species. Unexpected records of M. cf. macrocopa made in the Late Pleistocene of North Yakutia demonstrate that this group previously had a broader distribution range in North-Eastern Eurasia, but it subsequently suffered a mass extinction in that area. From the other side, the Old World lineage of M. macrocopa demonstrates expansion of its distribution in the New World. As an important component of freshwater biota of tropical and subtropical regions as well as regions with arid hot climate, moinids may harbor biogeographical vestiges.We hope that our data will serve as a basis for the special search and identification of their remains, as well as for their incorporation into paleoreconstructions for the tracking of different environmental changes.

Despite the important advances made in the taxonomy of water fleas (Crustacea: Cladocera), many taxa have not yet been revised. The genus Simocephalus Schoedler, 1858 (Anomopoda: Daphniidae) belongs to understudied groups. During the last forty years, several attempts have been made to use genetic approaches to estimate species diversity within Simocephalus. At the same time, investigations on morphology almost stopped after the last revision of Orlova-Bienkowskaja (2001). The lack of morphological data, even on the most widespread taxa, makes it difficult to apply the remains of this group to paleoecological reconstructions, although Simocephalus ephippia are common in subfossil sediments and fossils of different geological ages. We investigated more than 80 ephippia of recent representatives of the genus from Eurasia and North America, and 45 ephippia from Pleistocene sites of different ages on these two continents. For the first time, we have distinguished three main morphotypes based on the sculpture of the ephippia among the recent representatives. Ephippia of the vetulus-type are covered by polygonal hillocks of moderate height and with prominent processes. This morphotype is the most common in Eurasia, but it could be found on other continents, considering the distribution patterns of the S. vetulus species complex. Ephippia of the vetuloides-mixtus-type are covered by hillocks with processes strongly protruding above the ephippium surface. This morphotype is found only in the Asian part of Russia; it has more localized distribution than the vetulus-type. Ephippia of the serrulatus-type are covered by almost flat hillocks, or with hillocks of moderate height. This morphotype is found in both Eurasia and North America, which may confirm previous genetic data on a close relationship between serrulatus populations from the Eastern Palearctic and North America. Ephippia of the vetulus- and serrulatus-types are found in several Pleistocene localities. Due to lack of information about ornamentation patterns of Simocephalus ephippia of pre-Cenozoic age, we could not estimate the precise time of the morphotype separation. However we may conclude that in the Late Pleistocene the vetulus- and serrulatus-types were broadly distributed in Northern Eurasia and North America. Simocephalus ephippia demonstrate a morphological stasis at least since the Late Pleistocene, or even during longer time. In Maly Chukochiy Cape deposits (Republic Yakutia) we found a sole ephippium presumably belonging to an extinct taxon of Simocephalus. Eastern parts of Northern Eurasia had diverse communities of Simocephalus at the Pleistocene-Holocene boundary, and these then changed analogously to the transformation of Daphnia communities. In the course of our work, we obtained a large set of illustrations of Simocephalus ephippium morphology in different populations. We hope that our study will attract more attention to the taxonomy of modern Simocephalus and its Pleistocene-earlier Holocene subfossil ephippia.

A comparison of woolly rhinoceros (WR) (Coelodonta antiquitatis) individuals of different ages found at different times in Yakutia (one-year-old suckling (juvenis = infantulus), two 4–5-year-old juveniles (subadultus), 20-year-old (adultus) and 30-year-old females (adultus = senex), adult individual (adultus) of unknown sex) allows us to reconstruct the age-related changes in their hair coat. As the individual matures, the fur color apparently changed from light to dark brown, with a possible presence of local color spots (from light beige to reddish). The fur became more diverse (polymorphic), darker, longer, denser, and thicker due to a growth of the upper layer of hair (kemp: overhair and guard hairs) and dense underfur (downy hairs). The most powerful multilayered fur covered the croup area. Among the main hair microstructures studied using a scanning electron microscopy (SEM), dense cortex and multilayered cuticle with similar patterns were developed in the extinct WR and recent Indian rhinoceros (Rhinoceros unicornis). The main tendency of adaptation of the WR hair coat consisted of enhancing the mechanical strength of the fur, achieved due to uneven development of different hair structures (thick, coarse cuticle and cortex and weakly developed or absent less durable cellular medulla), as well as formation of an upper protective layer of coarse kemp. A multilayered nature of the thick fur (especially the presence of abundant underfur) provided the woolly rhinoceros hair coat with excellent heat-protective and mechanical properties, efficiently protecting these animals from climatic and traumatic external effects. A comparison of WR fur with the fur of large extinct ungulates of the Mammoth fauna (woolly mammoth (Mammutus primigenius†), extinct steppe bison (Bison priscus†) and muskox (Ovibos moschatus, existed since the time of the Mammoth fauna), bison (Bison bison), wisent (Bison bonasus), as well as cave lion (Panthera spelaea†)) reveals general patterns of adaptation of the hair coat of WR and other representatives of the Mammoth fauna to living in the harsh climatic conditions of the Ice Age in the Arctic.

As the first domestic species, dogs likely dispersed with different cultural groups during the Late Pleistocene and Holocene. To test this hypothesis, we analyzed 73 ancient dog genomes, including 17 newly sequenced individuals sampled from East Asia to the West Eurasian Steppe spanning nearly 10,000 years. Our results indicate correlations between the ancestry of dogs and specific ancient human populations from eastern Europe to Eastern Siberia, including Ancient Paleo-Siberians, Eastern hunter-gatherers, East Asians, and Steppe pastoralists. We also identify multiple shifts in the ancestry of dogs that coincide with specific dispersals of hunter-gatherers, farmers, and pastoralists. Combined, our results reveal the long-term and integral role that dogs played in a multitude of human societies.

In this study, we examine the dimensions of the nasal horns of woolly rhinoceroses and describe the longest rhino horn known to date, which was recently discovered in the permafrost of Yakutia. The extinct woolly rhinoceros is an iconic representative of the Late Pleistocene mammoth fauna of Eurasia, characterized by two huge keratinous horns. The nasal horn is considerably longer than the frontal one; it is laterally flattened and has a saber‐like shape, which is unparalleled among modern‐day rhinoceroses. The nasal horns of adult woolly rhinoceroses range in length along the anterior curvature from 68.5 to 134 cm (101.7 cm on average). Their mass varies between 2.5 and 11.4 kg (6 kg on average). Both of these values exceed those of all extant rhinoceroses. The record‐breaking nasal horn discovered in Yakutia last year reaches 164.7 cm along the anterior curvature and weighs ~9 kg. The relatively small size of the skull in this specimen indicates that it probably belonged to a rhinoceros female. This suggests that Coelodonta antiquitatis may have had the longest horns in females, similar to modern‐day African rhinoceroses. The number of periodic transverse bands (each of which consists of two, darker and lighter, keratin zones) along the length of the horn suggests that the discovered horn belonged to the oldest known woolly rhinoceros with an individual age of ≥40 years. Thus, this discovery not only provides insights into the morphological features of woolly rhinoceroses but also offers valuable information about their palaeoecology and sexual dimorphism.

In this study, we aimed to achieve three objectives: (1) to precisely characterize the body plans of Elephantidae and other large herbivorous mammals; (2) based on this analysis, to determine whether the body plans of the extinct woolly mammoth (Mammuthus primigenius) and steppe mammoth (M. trogontherii) differ from those of modern‐day Elephantidae: the Asian elephant (Elephas maximus), the African bush (Loxodonta africana), and forest (L. cyclotis) elephants; (3) to analyze how the body plans have changed in extant perissodactyls and proboscideans compared with their Paleogene ancestors. To accomplish this, we studied mammoth skeletons from the collections of Russian museums and compared this data with a large number of skeletons of extant elephantids, odd‐toed, and even‐toed ungulates, as well as their extinct relatives. We showed that three genera of Elephantidae are characterized by a homogeneous body plan, which is markedly different from other large herbivores. Elephantids break the interrelationship, that exists in artiodactyls and perissodactyls, between the total length of the head and neck on one side and the limb's segments on the other. Their limbs are very tall (inferior in this regard among large ungulates only to the giraffe), and, contrary to the other large herbivorous mammals, elongated due to the length of the proximal segments. This allows them to effectively utilize the principle of inverted pendulum (straight‐legged walking) in locomotion. The biggest differences in the body plan of mammoths compared with extant elephants are a markedly larger pelvis, elongated fore‐ and hindlimbs (due to the increased relative length of their proximal segments), and different proportions of the skull. The body plans of plesiomorphic Paleogene proboscideans and perissodactyls differed markedly from their descendants in every body part; these differences are related, on the one hand, to the allometric growth, and on the other hand, to the advancement of the locomotor apparatus in the course of their evolution. The most notable difference in the body plan between Paleogene proboscidean Moeritherium and extant Elephantidae is the ~2‐fold increase in relative limb height.

The history and palaeoecology of the steppe bison ( Bison priscus ) remain incompletely understood despite its widespread distribution. Using dental microwear textural analysis (DMTA) and vegetation modelling, we reconstructed the diet and assessed the habitat of steppe bison inhabiting Eurasia and Alaska since the Middle Pleistocene. During the Late Pleistocene, steppe bison occupied a variety of biome types: from the mosaic of temperate summergreen forest and steppe/temperate grassland (Serbia) to the tundra biomes (Siberia and Alaska). Despite the differences in the identified biome types, the diet of steppe bison did not differ significantly among populations in Eurasia. DMTA classified it as a mixed forager in all populations studied. The DMTA of Bb1 bison—a recently identified genetically extinct sister-clade of Bison bonasus —was typical of a highly grazing bovid species and differed from all B. priscus populations. The results of the study temper the common perception that steppe bison were grazers in steppe habitats. The dietary plasticity of the steppe bison was lower when compared with modern European bison and may have played an important role in its extinction, even in the stable tundra biome of eastern Siberia, where it has survived the longest in all of Eurasia.