G. G. Boeskorov

Species-specific responses of Late Quaternary megafauna to climate and humans

Despite decades of research, the roles of climate and humans in driving the dramatic extinctions of large-bodied mammals during the Late Quaternary period remain contentious. Here we use ancient DNA, species distribution models and the human fossil record to elucidate how climate and humans shaped the demographic history of woolly rhinoceros, woolly mammoth, wild horse, reindeer, bison and musk ox. We show that climate has been a major driver of population change over the past 50,000 years. However, each species responds differently to the effects of climatic shifts, habitat redistribution and human encroachment. Although climate change alone can explain the extinction of some species, such as Eurasian musk ox and woolly rhinoceros, a combination of climatic and anthropogenic effects appears to be responsible for the extinction of others, including Eurasian steppe bison and wild horse. We find no genetic signature or any distinctive range dynamics distinguishing extinct from surviving species, emphasizing the challenges associated with predicting future responses of extant mammals to climate and human-mediated habitat change.

Faunal record identifies Bering isthmus conditions as constraint to end-Pleistocene migration to the New World

Human colonization of the New World is generally believed to have entailed migrations from Siberia across the Bering isthmus. However, the limited archaeological record of these migrations means that details of the timing, cause and rate remain cryptic. Here, we have used a combination of ancient DNA, 14C dating, hydrogen and oxygen isotopes, and collagen sequencing to explore the colonization history of one of the few other large mammals to have successfully migrated into the Americas at this time: the North American elk (Cervus elaphus canadensis), also known as wapiti. We identify a long-term occupation of northeast Siberia, far beyond the species’s current Old World distribution. Migration into North America occurred at the end of the last glaciation, while the northeast Siberian source population became extinct only within the last 500 years. This finding is congruent with a similar proposed delay in human colonization, inferred from modern human mitochondrial DNA, and suggestions that the Bering isthmus was not traversable during parts of the Late Pleistocene. Our data imply a fundamental constraint in crossing Beringia, placing limits on the age and mode of human settlement in the Americas, and further establish the utility of ancient DNA in palaeontological investigations of species histories.

Preliminary analyses of the frozen mummies of mammoth (Mammuthus primigenius), bison (Bison priscus) and horse (Equus sp.) from the Yana‐Indigirka Lowland, Yakutia, Russia

The frozen bodies of a young woolly mammoth (Mammuthus primigenius), a wild horse (Equus sp.) and a steppe bison (Bison priscus) were recently found in the northern Yakutia (northeastern Siberia). All specimens have preserved bones, skin and soft tissues. Whereas the woolly mammoth and the Pleistocene horse were represented by partial frozen bodies, the steppe bison body was recovered in an absolutely complete state. All specimens were found frozen in the permafrost, with some of the tissues mummified. The wild horse and steppe bison are of Holocene age, and the mammoth is of Late Pleistocene age.

Past climate changes, population dynamics and the origin of Bison in Europe

BackgroundClimatic and environmental fluctuations as well as anthropogenic pressure have led to the extinction of much of Europe’s megafauna. The European bison or wisent (Bison bonasus), one of the last wild European large mammals, narrowly escaped extinction at the onset of the 20th century owing to hunting and habitat fragmentation. Little is known, however, about its origin, evolutionary history and population dynamics during the Pleistocene.ResultsThrough ancient DNA analysis we show that the emblematic European bison has experienced several waves of population expansion, contraction, and extinction during the last 50,000 years in Europe, culminating in a major reduction of genetic diversity during the Holocene. Fifty-seven complete and partial ancient mitogenomes from throughout Europe, the Caucasus, and Siberia reveal that three populations of wisent (Bison bonasus) and steppe bison (B. priscus) alternately occupied Western Europe, correlating with climate-induced environmental changes. The Late Pleistocene European steppe bison originated from northern Eurasia, whereas the modern wisent population emerged from a refuge in the southern Caucasus after the last glacial maximum. A population overlap during a transition period is reflected in ca. 36,000-year-old paintings in the French Chauvet cave. Bayesian analyses of these complete ancient mitogenomes yielded new dates of the various branching events during the evolution of Bison and its radiation with Bos, which lead us to propose that the genetic affiliation between the wisent and cattle mitogenomes result from incomplete lineage sorting rather than post-speciation gene flow.ConclusionThe paleogenetic analysis of bison remains from the last 50,000 years reveals the influence of climate changes on the dynamics of the various bison populations in Europe, only one of which survived into the Holocene, where it experienced severe reductions in its genetic diversity. The time depth and geographical scope of this study enables us to propose temperate Western Europe as a suitable biotope for the wisent compatible with its reintroduction.

Preliminary Study of a Mummified Woolly Rhinoceros from the Lower Reaches of the Kolyma River

Blum., 1799) (Fig. 1) wasfound on the right bank of the Lower Kolyma River, ina gold field at the upper reaches of the Malaya Filip-pova River (8 km east of the village of Cherskii of theNizhnekolymskii District of Yakutia). We studied theburial place on October 10, 2007, and the specimen inMarch, 2008, as it was brought to the MammothMuseum of the Institute of Applied Ecology of North,Yakutsk (IPES). Most of the mummified corpse waspreserved, including the left half of the trunk, with skinof the head and ear, the skull with the lower jaw, thefore and hind legs (Figs. 1–3). Small bunches of shortcoarse light brown wool are only preserved on lowersites of legs. The right side of the body and the rightlegs are lost (apparently, cut off by a bulldozer). Mostof the inner organs are lost; however, intestine is prob-ably partially preserved. The same locality has yielded anumber of specimens isolated from the trunk, i.e., the rightpelvis, the lower part of the right hind leg with soft tissues(Fig. 3b), and bones of the right foreleg (humerus, ulna,carpals, metacarpals, and two ungual phalanges). Hornshave not been found. The fragmentary genitals preservedin the specimen show that this is a female.The body measurements of this individual are ratherlarge, close to those of other adult female woolly rhi-noceroses (Table 1) [1]; the specimen weighs about900 kg; hence, during its life, the animal was about1.5 tons. The parietal length of the skull is 763 mm, thezygomatic width is 332 mm, the length of the uppertooth row is 217 mm. The mandible from the symphysisto the posterior edge of the articular process is 562 mmlong, the tooth row is 212 mm long, the ascendingramus measured from the apex of the articular processis 265 mm high. The teeth has wear signs; the majorsutures on the skull are obliterated; the nasal septum iscompletely ossified. These features, along with thebody and skull measurements, strongly suggest that therhinoceros from the vicinity of the village of Cherskiiwas an adult.The locality is situated on the left slope of east expo-sition at approximately 130 m above sea level. Thebone-bearing bed is at a depth of 5–9 m, composed offrozen dark gray loam of the Edoma Formation (glacialassemblage), with ice interbeds. Mostly loose, icy Qua-ternary deposits at the upper reaches of the Malaya Fil-ippova River form the strata about 15–17 m thick. Theburial place is at the junction of the northeastern part ofthe Kolyma Lowland and hilly spurs of the Anui Pla-teau, at about 200–630 m above sea level. According tothe soil geographical zonation, the area under study isat the boundary of the forest–tundra plain and theAlazeya–Yukagir plateau–tundra–taiga province of thetundra–forest subzone. Recent soils at the upperreaches of the Malaya Filippova River are formed oftypical cryogenic and taiga permafrost soils with vary-ing peaty and gleyey admixture. They show a high con-tent of organic matter, loamy particle-size distribution,neutral and subacid reaction, and high enzymaticpotential. Vegetation in the area studied belongs to thethin northern larch forest subzone [2]. In elevated sites,this is light larch forest, frequently with continuousmossy–lichen cover, dense undergrowth of five or sixwillow species, dwarf and Middendorf’s birches, inplaces, Manchurian alder, abundant low shrubs, andwith a small admixture of grasses and forbs. Hills arecovered with the dwarf stone pine. Lowered areas fre-quently have marshy moss–frutescent or grass–mossyopen woodlands.Paleoecological conditions in the habitat of theKolyma rhinoceros was reconstructed based on palyno-logical analysis; the ground sample comes from pri-

Study of Pollen and Spores from the Stomach of a Fossil Woolly Rhinoceros Found in the Lower Reaches of the Kolyma River

E). A study of the stomach contentsof the fossilized rhinoceros using palynological methods with the aim of establishing the particularities of itsdiet and recreating the paleofloristic conditions of theperiod of its existence was of great interest.A sample of the remnants of the stomach lump ofthe woolly rhinoceros was characterized by a high concentration of pollen and spores (more than1700 micrograins in one preparation). Most pollengrains were very well preserved.In the general spectrum, the pollen of grass plantspredominates (98.5%). Pollen from trees and bushesaccounts of 0.9%, and 0.6% are represented by spores(Table 1). The grass pollen composition is mainlyaccounted for by the pollen of Gramineae (45.9%)and Compositae (40.6%), in which wormwood pollendominates (40.1%). Up to 10 varieties of pollen can bedistinguished in the Gramineae pollen by morphological characteristics. They differ in size, grain shape,pore, and exine structure, etc. It is very difficult toclassify the Gramineae pollen down to the specieslevel, and this has not been done yet. Nonetheless,judging by the morphological particularities of thepollen, it can be assumed that it belongs to differentGramineae species. Wormwood pollen is also represented by various species; on the basis of its morphology, we assume that it is composed of

Identification of Hairs of the Wooly Mammoth Mammuthus primigenius and Wooly Rhinoceros Coelodonta antiquitatis Using Scanning Electron Microscopy

Hair of the woolly mammoth Mammuthus primige� nius Blumenbach, 1799 has been studied for many years. Judging from the ancient rock paintings, figu� rines, and preserved hair fragments, as well as from the data of numerous paleontological researches, the mammoth hair was long (up to 1 m or even longer), thick, multitiered, and with topographical differ� ences. The hair coat of the woolly rhinoceros (WR) Coelodonta antiquitatis Blumenbach, 1799 was also thick and long. The wool of both species was three� tiered: the most numerous downy hairs, which formed a thick underhair, the long and sparse intermediate (or guard) hairs, and the sparsest overhair giving fluffiness to the wool. The hairs grew in the skin singly and had sebaceous glands (1, 2). Tens of the dead mammoth bodies were found in permafrost, and the mammoth hair microstructure was the subject of numerous studies (3-6). Only a few overhairs have the fragmented medulla consisting of meshes irregular in shape and with jagged edges; they are loosely arranged along the hair axis. The mam� moth hair cuticle, which is not annular because the scales do not fully encircle the shaft, is heavily damaged as a rule, and the free edges of the scales are broken. The WR remnants with soft tissues are much more rarely found in the permafrost than the mammoth remnants; therefore, the WR woolly coat has been much less studied. Until now, no fundamental differ� ences have been found in the hair structure between recent rhinoceros species and WR: as in the mam� moth, rhinoceros hairs are deprived of medulla, have a mosaic cuticle pattern and the true cylindrical shaft. All of the main hair structures are nonspecific; there� fore, it is impossible to determine even generic affilia� tion of wool (7). The lack of hair coat and subcutane� ous fatty tissue in recent rhinoceros, as well as the presence of numerous large and actively secreting apo� crine glands are believed to be related to specific ther� moregulation in these inhabitants of tropics (8). Under the conditions of the Ice Age, the heavy hair coat of WR contributed to their survival.

New evidence for the existence of pleistocene cave bears in Arctic Siberia.

239 For a long time, cave bears Ursus (Spelearctos) spp. were considered to be typical representatives of bears that lived in Europe during the Pleistocene [1, 2]. Later, it has become clear that they also lived in the area of modern Israel, the Caucasus, South Siberia, Kyrgyzstan, and Korea [3–5]. Dental morphology and isotope data obtained indicate that cave bears ate predominantly plant food [1, 6]. Due to this, it was assumed that they were absent in northern Siberia, where omnivorous brown bears (Ursus arctos L.) replaced cave bears due to an influence of environ mental conditions [7].

Chronology and Faunal Remains of the Khayrgas Cave (Eastern Siberia, Russia)

The Khayrgas Cave in Yakutia (eastern Siberia) is one of the most important Upper Paleolithic sites in northern Asia, and has been the subject of extensive 14 C dating and study of mammal bones. The upper part of the cave sequence (Layers 2–4) dates to the Holocene (~4100–8200 BP), and the lower part (Layers 5–7) to the Late Pleistocene (~13,100–21,500 BP). In Layers 2–4, only extant animal species are known; ecologically they belong to a forest-type ecosystem. In Layers 5–7, several extinct species were identified, and the environment at that time corresponded to open and semi-open ecosystems. The Khayrgas Cave provides rare but reliable evidence of human occupation in the deep continental region of eastern Siberia at the Last Glacial Maximum, ~20,700–21,500 BP.

Adaptation of the woolly mammoth Mammuthus primigenius (Blumenbach, 1799) to habitat conditions in the glacial period

An analysis of the available data on the various adaptations of the woolly mammoth to the cryoarid conditions of the Ice Age is presented. Mammuthus primigenius had a set of specific anatomic–morphological (thick long three-row wool, small ears, a short tail, an adipose “hump”, a “hood”-like extension on the trunk, and wide soles of the feet) and physiological (reduced sensitivity to cold and a specific kind of lipid metabolism) ideoadaptations that provided safe existence and wide distribution of this species in the Northern Holarctic for a long time. The current data make it possible to refer the woolly mammoth to a highly specialized species of the Mammoth biome.