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Kahlke R.-D.,Senckenberg Research Institutes and Natural History Museums
Quaternary International | Year: 2015

The maximum geographic extension of fully developed woolly mammoth, Mammuthus primigenius, occurred during the last glacial period (MIS 5d-2), i.e. during the 110-14 ka interval. The mapping of the species' widest distribution reveals principal barriers to its expansion that were acting independent of short term environmental fluctuations. The maximum spread of M. primigenius was primarily controlled by the following trans-regional factors: (A) The configuration of inland glaciers; (B) The configuration of high mountain chains; (C) The configuration of semi-deserts and deserts; (D) The configuration of marine shorelines at year-round open water surfaces; (E) The exposure of continental shelf regions; and (F) The replacement of tundra-steppe by extended grasslands. Some of the biogeographic barriers were climate-independent; others were determined by long- or medium-term climatic processes. The effect of Eurasian and North American intra-continental steppes as obstacles to migration has not yet been fully elucidated.The verifiable area of the Late Pleistocene distribution range of M. primigenius, based on geomorphological data, comprises approximately 33,301,000 km2 (surface area). When taking the geographical distribution of a species as a measure of its success, the Late Pleistocene woolly mammoth was one of the most successful large herbivores of the Holarctic Mammoth Fauna. © 2015 Elsevier Ltd and INQUA. Source

Munoz-Fuentes V.,Uppsala University | Munoz-Fuentes V.,EBD Group | Munoz-Fuentes V.,Senckenberg Research Institutes and Natural History Museums | Linde Forsberg C.,Swedish University of Agricultural Sciences | And 2 more authors.
Theriogenology | Year: 2014

Sperm samples may be used for assisted reproductive technologies (e.g., farmed or endangered species) or as a source of haploid DNA or sperm-specific RNA. When ejaculated spermatozoa are not available or are very difficult to obtain, as is the case for most wild endangered species, the epididymides of dead animals (e.g., animals that have been found dead, shot by hunters or poachers, or that that require euthanasia in zoological collections) can be used as a source of sperm. Such epididymal sperm samples are usually contaminated with cellular debris, erythrocytes, leukocytes, and sometimes also bacteria. These contaminants may be sources of reactive oxygen species that damage spermatozoa during freezing or contribute undesired genetic material from diploid cells. We used single-layer centrifugation through a colloid formulation, Androcoll-C, to successfully separate wolf epididymal spermatozoa from contaminating cells and cellular debris in epididymal samples harvested from carcasses. Such a procedure may potentially be applied to epididymal sperm samples from other species. © 2014 Elsevier Inc. Source

Kahlke R.-D.,Senckenberg Research Institutes and Natural History Museums | Kaiser T.M.,University of Hamburg
Quaternary Science Reviews | Year: 2011

The so-called Hundsheim rhinoceros, Stephanorhinus hundsheimensis, was a very common faunal element of the Early to early Middle Pleistocene period in the western Palaearctic. In this study, individuals from two different central European populations of the Hundsheim rhinoceros were analysed in order to determine whether their local dietary signals could reflect differing food availability between the two populations, and whether such information could provide a better understanding of the ecological role of S. hundsheimensis within corresponding faunal assemblages, and of its principal subsistence strategy in the western Palaearctic. The mesowear traits observed in the studied S. hundsheimensis populations have been interpreted as representing biome-specific signals, indicating grassland vegetation at the site of Süßenborn, and dense to open forests at Voigtstedt (both localities in Germany). The analyses performed on the fossil rhino material demonstrate the most pronounced dietary variability ever established for a single herbivorous ungulate species by mesowear studies. This variability ranges from an attrition dominated grazing regime, to a one of predominantly browsing, and characterises S. hundsheimensis as the most ecologically tolerant rhinoceros of the Palaearctic Plio-Pleistocene. Although such dietary flexibility proved an effective enough subsistence strategy over a period of 600-900 ka (1.4/1.2-0.6/0.5 Myr) in the western Palaearctic, the situation changed dramatically after 0.6 Myr BP, when the new species of rhinoceroses, Stephanorhinus hemitoechus and Stephanorhinus kirchbergensis, appeared and started to compete for both the grass and the browse. For the generalist S. hundsheimensis, this bilateral interference was detrimental to its success in all of its habitats. The successful competition of specialised forms of rhinoceroses, which might have originated as a result of the development of 100 ka periodicity in the global climatic record, is proposed as the main reason for the extinction of S. hundsheimensis during the early Middle Pleistocene. © 2010 Elsevier Ltd. Source

Kahlke R.-D.,Senckenberg Research Institutes and Natural History Museums | Garcia N.,Complutense University of Madrid | Kostopoulos D.S.,Aristotle University of Thessaloniki | Lacombat F.,Musee Crozatier | And 4 more authors.
Quaternary Science Reviews | Year: 2011

Large-scale fluctuations in global climate and resulting changes in ecology had a profound effect on human evolution and dispersal. Though hominin remains are scarce, studies focussing on the more abundant records of fossil land mammal communities can contribute greatly to our knowledge of the palaeoenvironmental circumstances that influenced and directed the global spread of hominins. To produce a comprehensive and accurate account of the evolution of western Palaearctic habitat diversity between 2.6 and 0.4. Ma BP, information generated from large mammal communities from 221 key sites has been included in this study. The palaeoecological conditions of the western Palaearctic during the Early and early Middle Pleistocene were principally controlled by the following key factors: (1) a widespread trend of temperature decrease, (2) the periodicity of the global temperature record, (3) the intensity of single climatic stages, (4) the temporal pattern of climatic variation, (5) geographical position, and (6) the distribution of continental water resources. A general picture of the evolution of western Palaearctic habitat diversity saw the replacement of extensive forested terrain by an alternating sequence of varied savannah-like and forested habitats during the 2.6-1.8. Ma span, as well as an alternation between different types of predominantly open habitats between 1.8 and 1.2. Ma. Both of these processes were governed by 41. ka temperature periodicity. During the 1.2-0.9. Ma time span, irregular climatic fluctuations were more common and habitat variability increased. The subsequent 0.9-0.4. Ma interval, a period controlled by 100. ka periodicity, was by comparison more stable, with longer climatic cycles alternating between open and forested landscapes. During the entire Early and early Middle Pleistocene, assemblages of large mammal communities reveal a distinct trend of decreasing continentality between Eastern and South-Eastern Europe on the one hand, and South-Western and North-Western Europe on the other. This trend was due to the effect of the Atlantic Ocean, while in Southern Europe the relatively low continentality was balanced by influences from the Mediterranean Sea. When plotted against evidence of hominin occurrence, the data on western Palaearctic habitat diversity inferred from large mammal communities indicate clear environmental stimuli for the earliest human dispersal in Europe. These are: (1) a wide range of habitats, implying a high diversity of resources; (2) mild climates with low seasonality, implying a lack of strong environmental fluctuations. Around 1.8. Ma at the latest, hominins of African origin entered the western Palaearctic for the first time, taking advantage of the diversity of habitats and resources, particularly along large river systems. Their subsequent westward spread between 1.7 and 1.3. Ma was restricted to Mediterranean-influenced areas, which offered a high variability of habitats and relatively low seasonality. The increase in environmental diversity, which occurred from 1.2. Ma onwards, opened up South-Eastern and Eastern Europe for hominin occupation. According to the available records, North-Western and Central Europe were initially colonized during late Early to early Middle Pleistocene interglacials, when these regions experienced periods of low seasonality and considerable habitat diversity. © 2010 Elsevier Ltd. Source

Geismar J.,Senckenberg Research Institutes and Natural History Museums | Nowak C.,Senckenberg Research Institutes and Natural History Museums | Nowak C.,Biodiversity and Climate Research Center
Conservation Genetics Resources | Year: 2013

We developed thirteen microsatellite markers for the stonefly Brachytpera braueri, a rare aquatic insect. We compared a "traditional" approach yielding an enriched library by cloning of positive host cells, hybridising and Sanger sequencing of target fragments with a 454 next generation sequencing approach. From a total of 881 fragments containing a repeat motif thirteen polymorphic loci were developed and tested for two populations. Number of alleles ranged from 4 to 20 and values of heterozygosity varied from 0. 17 to 0. 91 (HO) and 0. 26 to 0. 91 (HE). The markers are essential to investigate the colonisation potential of freshwater insects. © 2012 Springer Science+Business Media Dordrecht. Source

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