Содержание: Том 17 (2) 2018 (отпечатан 21 December 2018)
Baigusheva V.S., Matishov G.G., Titov V.V.
Incomplete skull of a young elephant with dP4 and a fragmentary tusk were found in the alluvial deposits exposed in a sand pit near the settlement of Kagalnik. The age of the enclosing deposits correlates with the early Middle Pleistocene, the time range of the Tiraspol faunal complex of the Eastern Europe (= Cromerian), and the regional rodent biochron MQR 5. Two skeletons of Mammuthus trogontherii have been previously found in this area. The dental structure of the studied specimen evidences its attribution to M. trogontherii and demonstrate its difference from other taxa of mammuthoid elephants.
Boeskorov G.G., Tikhonov A.N., Protopopov A.V., Stepanov A.D., Plotnikov V.V., van der Plicht J., Shchelchkova M.V., Baryshnikov G.F.
This article discusses recent finds of Holocene polar bear and walrus from the northern regions of Russia. The ulna of a polar bear was found on Vaygach Island and radiocarbon dated to 1,971±25 BP (OxA-23631). This calibrates to 430–540 AD, taking into account the marine reservoir effect. The size of the bone is similar to that of a recent Ursus maritimus. The locality of the fossil bone is within the modern species range, which developed about two millennia ago. In 2014 a walrus tusk was found on the coast of New Siberia Island and is radiocarbon dated to 5,065±35 BP (GrA-62452). This calibrates to 3,510–3,370 BC, taking into account the marine reservoir effect. Its size and morphology are identical to that of an adult male of the subspecies Odobenus rosmarus laptevi. This subspecies populates the eastern parts of the Kara Sea, the entire Laptev Sea and the western parts of the East Siberian Sea. This new discovery could mean that populations of O. rosmarus laptevi inhabited the waters near the New Siberian Islands during the Middle Holocene, and that the present-day coastline of the Siberian Arctic Islands was already formed at that time.
Vestigial teeth of the Pacific walrus from the Chukotka Peninsula (Russia) were examined for 94 specimens. The following teeth were studied: the second upper and the third lower incisors, the fourth upper premolar, and the first upper and first lower molars. The upper second incisor is the largest among vestigial teeth and is less likely to be reabsorbed than the others. Growth duration for the majority of vestigial teeth is short (1–2 years). For most of the vestigial teeth, independent of the total number of cement layers and/or age of the walrus, only the enamel and partial upper part of dentine were worn off — without deforming any cementum layers. Generally the weight and width of the upper second incisor and the upper fourth premolar will increase relative to the number of annual cement layers added. For the majority of vestigial teeth examined, the number of cement layers coincided on pairs of teeth the same individual but seldom coincided with the number of cementum layers on other non-vestigial teeth. Because of irregular deposition of cementum layers, vestigial teeth should not be used for age determination of purposes.
Lissovsky A.A., Sheftel B.I., Stakheev V.V., Ermakov O.A., Smirnov D.G., Glazov D.M., Strelnikov D.P., Ekonomov A.V., Titov S.V., Obolenskaya E.V., Kozlov Y.A., Saveljev A.P.
The current capacity for the purposeful study of the mammalian fauna of Russia using public databases is discussed. A list of species of Russian fauna compiled under united principles is lacking and the lists of species published in different departments are inconsistent. Systems that can monitor changes in the qualitative or quantitative composition of the fauna are not yet sufficiently refined. The systematization of previously accumulated faunal data requires the involvement of qualified taxonomists. Nevertheless, initial work on the “Mammals of Russia” database, which currently contains 16 512 records on 235 species of mammals, has allowed us to positively assess the prospects for further ordering of faunal information within the country.
Volkova V.R., Lissovsky A.A.
Variation in the shape of the occlusal surface of permanent teeth was examined in 102 skulls of four species of pikas. Variance components analysis was carried out on Procrustean coordinates retrieved from 71 and 65 landmarks positioned on the lower and upper teeth rows respectively. The main variance was related to the within-group variation, which indicates general instability in the shape of the enamel loops. Sexual variation explained the smallest amount of variance among all factors examined. The highest percentage of age-related variation was found in the premolars of both teeth rows, especially in p3 and P3. The amount of variance due to interspecies variation was relatively low in all analyses, even in the anterior part of p3, which is regularly recommended for the identification of pikas species. There was no evidence of a phylogenetic signal either. Thus we suggest more careful investigation of the role of features of the shape of teeth occlusal surface for species identification.
Yağcı T., Şen E., Gurbanov R.R.
A total of 36 samples of 2n = 54 and 2n = 60 cytotypes of Nannospalax xanthodon, distributed in the Central Anatolia region of Turkey, were analyzed for the first time by using inter-simple sequence repeat-polymerase chain reaction (ISSR-PCR) technique. The analysis revealed 112 ISSR bands, 101 of which were polymorphic. Seven ISSR primers ((AG)8 T, (GGAGA)5, (GACA)4, (TG)8 A, (CAG)5 GC, (CAG)4 AC and (GA)8 AC)) were optimized from total 20 primers. (AG)8 T and (GA)8 AC primers were most informative to distinguish cytotypes by producing specific bands for 2n = 54 and 2n = 60. The cytotypes in genetically close relationships were separated into three different groups by UPGMA cluster analysis, in which, the highest genetic diversity was measured for 2n = 60. Our results showed that ISSR markers can be used as a simple and reliable molecular tool, for the estimation of genetic diversity in cytotypes of Nannospalax at low range genetic distances.