Mid-holocene Brown Bear (Ursus arctos) from the Bolshoy Lyakhovsky Island (New Siberian Islands).

A morphological description is provided for a unique find of a frozen mummified subfossil brown bear (Ursus arctos L., 1758), found for the first time ever. The find is a well-preserved bear carcass of approximately 3500 years in age. Results of computed tomography and DNA testing are discussed.

New Data on the Ecology of the Fossil Don Hare Lepus tanaiticus Gureev, 1964.

A spore and pollen research was performed for the first time to study the contents of the gastrointestinal tracts (GITs) and sediments containing frozen mummies of the fossil Don hare from the Upper Pleistocene ice complex of the Verkhoyansk district of Yakutia. Radiocarbon dating (C14) revealed that the hares lived during the Karginian Interstadial of the Late Pleistocene, 32.5 thousand years ago (calibrated date). The results expanded the understanding of the ecology of extinct Lepus tanaiticus. The species was assumed to live in cold steppes dominated by xerophytic communities, as well as in grass-forb and sedge-forb meadows. Herbaceous plants mostly constituted the winter diet of Don hare in contrast to the modern mountain hare L. timidus, which feeds mainly on branches and bark of trees and shrubs in winter.

Dyuktai Goose (Anser djuktaiensis) and Hooded Crane (Grus monacha) from the Pleistocene of Central Yakutia.

Bird bones from the Late Pleistocene (31-24 kyr) Ikhine-2 site (Central Yakutia), one of the key Upper Paleolithic sites in northeastern Siberia, have first been studied. This is the northernmost and the oldest bird association in the Pleistocene of Eastern Siberia. Among the bone materials available, the coracoids of the extinct Dyuktai goose (Anser djuktaiensis) and the hooded crane (Grus monacha) are of particular interest. Dyuktai goose is a large representative of the mammoth fauna, originally described from younger deposits (12-13 kyr) in southeastern Yakutia. This is the second find of this species in Russia, which significantly expands our understanding of the geography and time of its distribution. The hooded crane, a rare modern species with a limited habitat area, has first been found in paleontological record. This find indicates the northern distribution of this species during the Late Pleistocene Karginian interstadial. Bones of Anas crecca and Larus canus have also been found at the site.

First Description of the Fur of Two Cubs of Fossil Cave Lion Panthera spelaea (Goldfuss, 1810) Found in Yakutia in 2017 and 2018.

The first description of well-preserved fur of one male and one female cubs of the fossil cave lion Panthera spelaea (finds of 2017-2018, Semyuelyakh River, Yakutia, Russia) is presented in comparison with the fur of two cubs (a male and a female) of the extant African lion P. leo and adult lions of both species: the color, differentiation, configuration, microstructure, and internal design of hair of different categories are considered. The coat of the cave lion is similar but not identical to that of the African lion, because it contains a high thick undercoat of spiral-shaped thick and airy down hair. This difference is most pronounced in the cave lion cubs, in which, however, the fur is not differentiated to the same extent as in the adult. The microstructure of hair is species-specific and subject to intraspecific age-related variability. Adaptive features of the hair structure in the cave lion are noted.

Initial data on biological activity of taiga-steppe soils in the lower reaches of the Kolyma River.

Microbiological and enzyme activities of extrazonal taiga-steppe soils in the lower reaches of the Kolyma River have been studied for the first time. Contrary to north-taiga cryometamorphic soils, predominating in the area, microbial cenoses under herb-sedge petrophytic and grass-sagebrush-herb thermophytic steppes are characterized by features typical for arid soils. The saturation of the soil profile with microorganisms is greater, and the development of actinomycetes is more intensive. The enzyme complex is characterized by high activity of dehydrogenases.

New data on the distribution and taxonomy of fossil Soergel's ox (Soergelia sp., Bovidae, Artiodactyla, Mammalia) in Yakutia.

Novel findings of fossil remains of the extinct artiodactyl Soergel's ox, as well as some findings that were not analyzed previously, are presented in the article. Soergelia remains are extremely rare; therefore, the species range of these animals remains uncharacterized by now and the taxonomic positions of some findings are not clear. Analysis of the new material extends the knowledge on the species range and the limits of morphological variation of the Soergel's ox and allowed a more precise assessment of the taxonomic position of the findings from Yakutia.

Hair microstructure of the first time found calf of woolly rhinoceros Coelodonta antiquitatis.

Hair microstructure of the first calf of the woolly rhinoceros Coelodonta antiquitatis found in Sakha in 2014 (the neck and hind leg hair) was examined by the light and electron scanning microscopy. The calf hair features were compared with those of two adults studied earlier. The calf coat color was much lighter than in adults, from pale ashy to blond. The extent of hair differentiation, dimensional and pigmentation indices were lower in the calf than in adult rhinoceroses. There was no medulla in the calf hairs, while in those of adults it was occasionally found. The cortical and cuticular layer microstructure was similar in all the animals compared. In both calf and adult hairs, there were traces of mechanical damage.

Comparative phylogeography and demographic history of the wood lemming (Myopus schisticolor): implications for late Quaternary history of the taiga species in Eurasia.

The association between demographic history, genealogy and geographical distribution of mitochondrial DNA cytochrome b haplotypes was studied in the wood lemming (Myopus schisticolor), a species that is closely associated with the boreal forest of the Eurasian taiga zone from Scandinavia to the Pacific coast. Except for a major phylogeographic discontinuity (0.9% nucleotide divergence) in southeastern Siberia, only shallow regional genetic structure was detected across northern Eurasia. Genetic signs of demographic expansions imply that successive range contractions and expansions on different spatial scales represented the primary historical events that shaped geographical patterns of genetic variation. Comparison of phylogeographic structure across a taxonomically diverse array of other species that are ecologically associated with the taiga forest revealed similar patterns and identified two general aspects. First, the major south-north phylogeographic discontinuity observed in five out of six species studied in southeastern Siberia and the Far East implies vicariant separation in two different refugial areas. The limited distribution range of the southeastern lineages provides no evidence of the importance of the putative southeastern refugial area for postglacial colonization of northern Eurasia by boreal forest species. Second, the lack of phylogeographic structure associated with significant reciprocal monophyly and genetic signatures of demographic expansion in all nine boreal forest animal species studied to date across most of northern Eurasia imply contraction of each species to a single refugial area during the late Pleistocene followed by range expansion on a continental scale. Similar phylogeographic patterns observed in this taxonomically diverse set of organisms with different life histories and dispersal potentials reflect the historical dynamics of their shared environment, the taiga forest in northern Eurasia.

[Genetic diversity of moose (Alces alces L.) in Eurasia]. / Geneticheskoe raznoobrazie losia (Alces alces L.) v Evrazii.

Polymorphism of nucleotide sequence of D-loop fragment of the mitochondrial DNA was studied in 20 moose from several local populations on the territory of Eurasia. Three main haplotype variants of D-loop were detected by molecular phylogenetic method, which formed three clusters named European, Asian and American. Intraspecies variation in the length of HVSI of D-loop of the mitochondrial DNA of moose was revealed. In the Far Eastern and Yakutian moose, haplotypes with a 75-bp deletion were found, which were most similar with haplotypes (also with the deletion), earlier observed in North American moose [1]. The highest diversity of the haplotypes of mitochondrial DNA is characteristic of Yakutia and the Far East (where three haplotype variants were found), which demonstrates the probable role of the region as the center of the species or as the region of ancient population mixture. The geographic region might be considered as a probable source of ancient moose migrations from Asia to America, basing on the data of distribution of mitochondrial haplotypes of D-loop and alleles of MhcAlal-DRB1. Divergence of nucleotide sequences of haplotypes with the 75-bp deletion (forming the American cluster on the phylogenetic tree) was the lowest (0.4%), which evidences respectively recent origin of the group of haplotypes. In Europe, only haplotypes of mitochondrial DNA referred to European variant were observed. Basing on analysis of variation of nucleotide sequences of D-loop, exon 4 of kappa-Casein and exon 2 of MhcALal-DRB1, we demonstrated that Eurasian moose studied belong to the unique species, which has probably passed through a bottle neck. The time of the origin of modern diversity of D-loop haplotypes of the species was estimated as 0.075-0.15 Myr ago.

[Genetic differentiation of Caucasian wood mice: comparison of isozymic, chromosomal and molecular divergence]. / Geneticheskaia differentsiatsiia lesnykh myshei Kavkaza: sravnenie izozimnoi, khromosomnoi i molekuliarnoi divergentsii.

Data on the complex genetic analysis of three sympatric species of Caucasian wood mice, Apodemus ponticus, A. fulvipectus, and A. uralensis are presented. A high degree of genetic differentiation at the isozymic, karyological and molecular (nuclear DNA) levels was revealed. The genetic distances between each pair of species varied significantly within a wide range depending on the analyzed level of the organization of genetic material. Mean values of genetic divergence from one species to another were also variable. These findings indicated that evolution of chromosomes was slower than that of isozymes, and the degree of species divergence was similar on cytogenetic and molecular levels. They also suggested that the rates of species evolution could vary in different phyletic lineages and on different levels of organization. Some phyletic lineages of Apodemus could be distinguished by different directions of evolution.

[Chromosomal differences in moose (Mammalia, Artiodactyla, Alces alces L.)]. / Khromsomnye razlichiia u losei (Mammalia, Artiodactyla, Alces alces L.)

Earlier studies on differences in moose (Alces alces) chromosome sets concerned only European (Scandinavia, Finland, the Volga region, and western Siberia) and American (the United States and Canada) forms. The first group had a 68-chromosome set, and the second group, a 70-chromosome set. These differences were considered interspecies chromosomal polymorphism. However, the chromosome number in A. alces living in eastern and northeastern Siberia remains unknown, although these data are important for elucidation of the geographical variation of karyotypes of moose from genus Alces. Four moose from different regions of Sakha were studied. It was found that their karyotypes contained 70 chromosomes; i.e., they were similar to the American form. These data indicate a strong differentiation within the species. Two chromosomal forms can be distinguished: the European one (2n = 68) living in Europe and western Siberia and the American one (2n = 70) living in North America, the Far East, and eastern Siberia. The existence of two forms is confirmed by data on their morphology, sound signals, electrophoretic mobility of proteins, and differences in nutrition. These results indicate that long-term isolation of European and American moose led to the high divergence between these two forms; therefore, they can be considered different species.