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1.
Data from the mammal fauna of the North Urals during the Late Pleistocene and Holocene are synthesised. Analysis of differentiation the degree of small- and large-mammal faunas during this time has been undertaken. Only differences of mammal species composition were significant between the Late Pleistocene and Holocene complexes, and within these complexes, the distinction between faunas was insignificant. The transition from the Late Pleistocene to the Holocene complex small-mammal faunas occurred in the Middle Late Valdai due to expansion of the forest species. In large-mammal faunas, the process was recorded later (in Dryas 3-Early Holocene) because of the extinction of some species and others that changed their areas of occupation.  相似文献   

2.
中国北方晚更新世哺乳类动物群的划分及其地理分布   总被引:3,自引:0,他引:3  
郑家坚  徐钦琦 《地层学杂志》1992,16(3):170-181,190
<正> 新第三纪以来,由于青藏高原、喜马拉雅山脉与西部山脉的隆起,我国形成了西高东低的地形特点,导致了气候和环境的变迁,明显地影响了中国哺乳动物的分布。在晚更新世,中国南北动物群分化逐渐扩大,动物群更替尤为频繁。中国晚更新世地层及动物群的研究已有一段相当长的历史,发现了众多重要的遗址和化石地点,积累了丰富的资料。笔者综合有关资料,对我国北方晚更新世动物群,特别是猛犸象-披毛犀动物群的划分、地  相似文献   

3.
临夏盆地晚新生代哺乳动物群演替与青藏高原隆升背景   总被引:16,自引:0,他引:16  
邓涛 《第四纪研究》2004,24(4):413-420
临夏盆地的晚新生代沉积中富含哺乳动物化石,以晚渐新世巨犀动物群、中中新世铲齿象动物群、晚中新世三趾马动物群和早更新世真马动物群的化石最为丰富。晚新生代是青藏高原快速隆升的时期,临夏盆地的4个主要哺乳动物群在构造剧烈变化的背景下发生了显著的更替。通过对不同动物群所代表的生态特征的分析,恢复了临夏盆地晚新生代以来的气候环境演变过程:晚渐新世以温暖湿润的森林环境为主,间杂有一些开阔地带;中中新世的森林更加茂密,水体更加丰富;晚中新世演变为炎热半干旱的稀树草原环境,季节性变化加强;早更新世气候寒冷而干燥,并伴有显著的海拔升高。青藏高原在晚渐新世的隆升幅度还不足以阻挡大型哺乳动物在高原南北的交流,但到中中新世已成为明显的障碍,至晚中新世对动物迁徙的阻碍作用更加突出,而临夏盆地在早更新世已经达到相当大的高度,产生了一个高原或高山的动物群  相似文献   

4.
Systematic studies of the Pleistocene mammal assemblages of Eastern Europe have been carried out for more than a century, and they elucidated evolutionary changes and ascertained chronological sequence of the faunas. The available evidence on fossil mammals from Eastern Europe allows differentiation of 7 complexes of large mammals. These complexes represent 15 assemblages and their phases distinguished for small mammals. The appearance of new taxa of different rank provides the basis for identification of the principal stages in mammal evolution. Multi-disciplinary studies of fossil mammal localities have made it possible to correlate theriological data with the main events of the Pleistocene (such as glacials and interglacials) by comparison between geological, geochronological and palaeontological data.Interglacial and periglacial mammal faunas of different age have been defined on the basis of their structural characteristics and geographical distribution. Two types of mammal assemblages are recognised: zonal interglacial and periglacial assemblages specific to glacial periods. In the first type, each zonal assemblage is dominated by a single ecological group of mammals. A distinctive feature of the second type is the co-existence of animals belonging to different ecological groups and inhabiting different natural environments.  相似文献   

5.
Evidence in the world’s ocean current system indicates an abrupt cooling from 34.1 to 33.6?Ma across the Eocene–Oligocene boundary at 33.9?Ma. The remarkable cooling period in the ocean, called the Eocene–Oligocene transition (EOT), is correlated with pronounced mammalian faunal replacement as shown in terrestrial fossil records. For the first time within Asia, a section is magnetostratigraphically dated that also produces mammalian fossils that span the Late Eocene—Early Oligocene transition. Three fossil assemblages revealed through the EOT (34.8, 33.7, and 30.4?Ma) demonstrate that perissodactyl faunas were abruptly replaced by rodent/lagomorph-dominant faunas during climate cooling, and that changes in mammalian communities were accelerated by aridification in central Asia. Three fossil assemblages (34.8, 33.7, and 30.4?Ma) within the north Junggar Basin (Burqin section) tied to this magnetostratigraphically dated section, reveal that perissodactyl faunas were abruptly replaced by rodent/lagomorph-dominant faunas during climate cooling, and that changes in mammalian communities were accelerated by aridification in central Asia. The biotic reorganization events described in the Burqin section are comparable to the Grande Coupure in Europe and the Mongolian Remodeling of mammalian communities. That is, the faunal transition was nearly simultaneous all over the world and mirrored global climatic changes with regional factors playing only a secondary role.  相似文献   

6.
Deer species provide a valuable biostratigraphical tool through Cromer Forest-bed times, due particularly to species turnover between the Early and early Middle Pleistocene. This study is based on the reidentification of 348 fossil antlers. The provenance of most large mammal fossils from the CF-bF, collected over 150 years, was recorded only by the nearest coastal village. None the less, analysis of the cervid taxa by these ‘localities’ reveals interesting patterns. The fauna of the West Runton Freshwater Bed is of early Middle Pleistocene complexion, and that from the foreshore at East Runton is of Early Pleistocene. Pure or nearly pure early Middle Pleistocene assemblages also occur at Kessingland-Pakefield and at Trimingham. At Overstrand, Sidestrand, Mundesley, Bacton and Happisburgh, there is a mixture of Early and early Middle Pleistocene elements. Analysis of Savin's data shows that fossils of earlier species were generally found further down the beach than those of later ones. Late nineteenth century geological surveys, made when bone collecting was at its peak, give additional information about fossil horizons, which in several cases can be related to modern stratigraphical units. Most Early Pleistocene large-mammal bones came from Pastonian conglomerates, in contrast to small-mammal and molluscan assemblages mostly extracted from Pre-Pastonian Crag. However, the diversity of Early Pleistocene CF-bF cervid species in comparison with continental faunas, and their pattern of distribution between sites, suggests they may span more than one chronostratigraphic stage. Early Middle Pleistocene assemblages came from strata now referred to the Cromerian, and the differing proportions of taxa between sites provide limited evidence of time-transgression.  相似文献   

7.
The wild horse Equus ferus was one of the most frequent species of the Late Pleistocene large ungulate fauna in Eurasia and played an important role in the subsistence of human groups, especially at the end the Late Glacial. It is frequently assumed that E. ferus became extinct in Europe at the beginning of the Holocene because of the development of woodlands and loss of open habitats. Because of its preference for open habitats and in spite of its adaptability, the appearance or disappearance of the wild horse could therefore be a suitable palaeoecological indicator for the opening of the Holocene primeval woodlands. We revised the dating and reliability of the subfossil record and dated several bones by atomic mass spectrometry 14C dating. From the beginning of the Holocene (9600 cal a BC) to the end of the Atlantic Period (3750 cal a BC) there are 207 archaeological sites with wild horse records available in Europe. E. ferus survived the Pleistocene Holocene transition in Europe, but the spatiotemporal dynamics of populations fluctuated remarkably in the early and middle Holocene. Small and sparse populations increasingly became extinct during the early Holocene, until between 7100 and 5500 cal a BC the wild horse was almost absent in central parts of the European Lowlands. Particular conditions in natural open patches in the canopy forests, chalklands and floodplains may have maintained the local survival of the horse in some regions of the Lowlands, however. In the Late Atlantic, between 5500 and 3750 cal a BC the range of the wild horse was again extended. It re‐immigrated into central and western Europe, probably as a consequence of increasing landscape opening by Neolithic peoples. The data presented here may be a valuable part of the debate on the degree of openness of the early and middle Holocene landscape. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

8.
This paper considers the data on new findings of mammoth fauna remains in the Middle Lena basin used to specify the species composition of large Late Neopleistocene mammals represented by eleven species. The obtained range of radiocarbon dates made it possible to state that mass burials of Pleistocene mammal remains were formed in the region during the Karginsk Interstadial (24 000–55 000 years ago).  相似文献   

9.
泥河湾地区晚上新世一个新的地层单位——稻地组   总被引:4,自引:1,他引:4  
本文记述了河北泥河湾盆地的一个新的地层单位——稻地组。在四个实测剖面上对稻地组进行了分层描述,根据其岩性、化石特征、及其与上下地层接触关系,确定了该地层组的含义,并对其时代(晚上新世)作了讨论。  相似文献   

10.
The causes of large animal extinctions at the end of the Pleistocene remain a hotly debated topic focused primarily on the effects of human over hunting and climate change. Here we examine multiple, large radiocarbon data sets for humans and extinct proboscideans and explore how variation in their temporal and geographic distributions were related prior to proboscidean extinction. These data include 4532 archaeological determinations from Europe and Siberia and 1177 mammoth and mastodont determinations from Europe, Siberia, and North America. All span the period from 45,000 to 12,000 calendar years BP. We show that while the geographic ranges of dated human occupations and proboscidean remains overlap across the terminal Pleistocene of the Old World, the two groups remain largely segregated and increases in the frequency of human occupations do not coincide with declines in proboscidean remains. Prior to the Last Glacial Maximum (LGM; ca 21,000 years BP), archaeological 14C determinations increase slightly in frequency worldwide while the frequency of dated proboscidean remains varies depending on taxon and location. After the LGM, both sympatric and allopatric groups of humans and proboscideans increase sharply as climatic conditions ameliorate. Post-LGM radiocarbon frequencies among proboscideans peak at different times, also depending upon taxon and location. Woolly mammoths in Beringia reach a maximum and then decline beginning between 16,000 and 15,500 years BP, woolly mammoths in Europe and Siberia ca 14,500 and 13,500 BP, and Columbian mammoth and American mastodont only after 13,000 BP. Declines among woolly mammoths appear to coincide with the restructuring of biotic communities following the Pleistocene–Holocene transition.  相似文献   

11.
The shoreline of the Taganrog Gulf of the Azov Sea at the mouth of Don River provides a series of extended Upper Pliocene and Quaternary sections that have been actively studied in the last century. This extraglacial region had a complex sedimentary history combining subaerial aggradation with marine, fluvial, and deltaic sedimentation. The well-exposed stratigraphical sequence and abundant palaeontological record continuously attract geologists and highlight the region as one of international importance for the addressing of numerous problems of Late Pliocene and Quaternary stratigraphy and palaeogeography. Fossil mammalian faunas of the region include important Eurasian biostratigraphical markers such as Stenocranius ex gr. hintoni-gregaloides, Lagurini spp., and Mimomys savini. For many years, fossil remains of mammals provide decisive clues to the geological history of the region. Recent geological studies of reference sections have provided data on small mammals, palaeomagnetism and palaeogeographical reconstructions in the northeastern part of the Azovian Region. Mammalian assemblages indicate the presence of the Late Pliocene, late Early Pleistocene, Middle Pleistocene and Late Pleistocene levels and, in addition, provide a clear biostratigraphical context for the Early Middle Pleistocene transition.  相似文献   

12.
Cold-adapted large mammal populations spread southward during the coldest and driest phases of the Late Pleistocene reaching the Iberian Peninsula. Presence of woolly rhinoceros (Coelodonta antiquitatis) can be identified from 23 Iberian sites, which is compiled and analyzed herein, and the fossil specimens from seven of these sites are described here for first time.Morphological and biometrical analyses demonstrate that the Iberian woolly rhinoceros did not significantly differ from individuals of other European populations, but represent the westernmost part of a continuous Eurasian belt of distribution.The first presence of woolly rhino in the Iberian Peninsula has been identified during the late Middle Pleistocene and early Late Pleistocene. However, the highest abundance of this species is recorded during MIS 3 and 2. The latest Iberian occurrences can be dated around 20 ka BP. The presence of woolly rhinoceros in the Iberian Peninsula correlates with periods of extreme dry and cold climatic conditions documented in Iberian terrestrial and marine sediment sequences.From a palaeobiogeographic point of view, the maximum southern spread of C. antiquitatis on the Iberian Peninsula was registered during the late Middle Pleistocene or early Late Pleistocene, reaching the latitude of Madrid (about 40°N). Subsequently, during MIS 3 and 2, all Iberian finds were restricted to the Northern regions of Iberia (Cantabrian area and Catalonia). The southern expansion of C. antiquitatis during the Late Pleistocene in the Iberian Peninsula reached similar latitudes to other Eurasian regions.The ecological composition of fossil assemblages with presence of woolly rhinoceros was statistically analyzed. Results show that temperate ungulate species are predominant at Iberian assemblages, resulting in a particular mixture of temperate and cold elements different of the typical Eurasian cold-adapted faunal associations. This particular situation suggests two possible explanations: a) Eventual migrations during the coldest time spans, resulting in a mixing of cold and temperate faunas, instead a faunal replacing; b) Persistence of woolly rhinoceros populations in the Iberian Peninsula during interglacial episodes confined at cryptic southern refugia.  相似文献   

13.
The 121 local faunas of large mammals from Late Pleistocene sites of the South (56–51°N), Middle (59–56°N) and North (64–59°N) Urals have been studied. All local faunas were combined into eight chronological groups on the basis of radiocarbon dates and the evolutionary level of rodents present in them. On the basis of species composition analysis of the faunas, three chronological complexes have been distinguished: Mikulino, Early–Middle Valdai and Late Valdai. The first is characterized by the presence of Hystrix vinogradovi and Ursus thibetanus; the second, by the presence of a large form of horse (Equus (E.) cf. latipes), Crocuta crocuta, Ursus spelaeus and U. savini; the third, by the presence of a small horse (E. uralensis) and absence of U. spelaeus, U. savini and C. crocuta. The latter two complexes were represented by three geographical variants: southern (South Urals), northern (North Urals) and transitional (Middle Urals). Differences between theriocomplexes are related to changes in morphology and areas and extinctions of a series of species. The existence of chronological theriocomplexes and their geographical variants was determined by chronological and geographical change in structure of paleophytocoenoses. It should be noted that the role of human in changes of chronological complexes and species extinctions in the Late Pleistocene has not been demonstrated in the Urals. In the Urals U. savini probably became extinct at the end of the Middle Valdai, C. crocuta at the beginning of the last glacial maximum (LGM), U. spelaeus at the end of the LGM, Coelodonta antiquitatis at the beginning of the Preboreal and Megaloceros giganteus at the middle of the Atlantic.  相似文献   

14.
New TIMS dates from British sites underpin and extend the growing model of mammalian faunal history during the Late Pleistocene. The sequence of British faunas during the three successive warm phases of MIS 5 presents a challenging model in which the mammal faunas of the first two temperate phases, 5e and 5c is dominated by species of a classically interglacial character, while that of the final phase, sub‐stage 5a, is dominated by bison and reindeer. This we see as the ‘cold fauna’ appearing in Britain during the cool isotope sub‐stage 5b and subsequently isolated by the rising sea level of isotope sub‐stage 5a. All these three faunas are true island faunas. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

15.
过去认为涝池河—阳郭动物群的时代相当或稍晚于泥河湾动物群,早于公王岭动物群,厚镇涝池河动物群的时代与公王岭动物群的一致。但各动物群的层位及在动物群演化上所处的位置表明涝池河—阳郭动物群的时代应与公王岭动物群的一致,比泥河湾动物群的晚,而厚镇涝池河动物群的时代应与陈家窝动物群的相当。重新厘定了公王岭期与陈家窝期的涵义,认为蓝田黄土地层中、早更新统的界线应划在S8与L9交界处。  相似文献   

16.
《Quaternary Science Reviews》1999,18(10-11):1151-1171
We constructed a radiometrically calibrated proxy record of Late Pleistocene and Holocene climate change exceeding 230,000 yr duration, using pollen profiles from two cores taken through age-equivalent dry lakes—one core having greater age control (via 230Th alpha mass-spectrometry) and the other having greater stratigraphic completeness. The better dated of these two serial pollen records (Searles Lake) served as a reference section for improving the effective radiometric age control in a nearby and more complete pollen record (Owens Lake) because they: (1) are situated ∼90 km apart in the same drainage system (on, and immediately leeward of, the eastern flank of the Sierra Nevada), and (2) preserved strikingly similar pollen profiles and concordant sequences of sedimentological changes. Pollen assemblages from both lakes are well preserved and diverse, and document serial changes in Late Pleistocene and Holocene plant zone distribution and composition in the westernmost Great Basin; they consist of taxa now inhabiting montane forest, woodland, steppe, and desert-scrub environments. The studied core intervals are interpreted here to be the terrestrial equivalent of marine δ18O stages 1 through 9; these pollen profiles now appear to be among the best radiometrically dated Late Pleistocene records of terrestrial climate change known.  相似文献   

17.
Here, we present and discuss results from geo‐archaeological and palaeo‐zoological investigations at the Palaeolithic site Pymva Shor, in the Russian Arctic. As many as 3324 vertebrate fauna remains were recovered during two excavations. This includes bones of mammals, birds and fish. Radiocarbon dates were obtained from 26 specimens. The results show ages in the range 30–3 cal. ka BP. Hare and reindeer are the best represented amongst the identified mammalian species, whilst ptarmigan and various wader species dominate the avian bones. The Pleistocene assemblage includes herbivorous herd animals such as horse, bison and musk ox. These species are typical of the treeless tundra‐steppe landscape that existed during the Lateglacial. Of particular interest is a cave lion specimen that has been radiocarbon dated to approximately 15.5 cal. ka BP. According to our knowledge, this is one of the latest dated examples of this species in Eurasia. The faunal composition in the Holocene assemblage is strikingly different and includes distinct forest taxa such as beaver and pine marten. The avifauna also supports a forested environment with the presence of black grouse. A few stone artefacts were found within the strata, and have been radiocarbon dated to 16–15 cal. ka BP, suggesting that there were humans in the Pymva Shore area at that time. We identified impact notches and cut marks on some radiocarbon‐dated reindeer and bison bones, showing that humans were present twice during the Younger Dryas period. A fourth occupation phase is identified during the mid‐Holocene (6–5 cal. ka BP). We also investigated river terraces and obtained a series of luminescence dates. These have been used to reconstruct the geological history and the relationship to the find‐bearing strata.  相似文献   

18.
Human subsistence systems in the Pampa and Patagonia regions evolved from generalists during the Late Pleistocene/Early Holocene to specialists during the Middle Holocene, according to diversity and relative taxonomic richness counts. The general hypothesis is summarized as follows: 1) at the end of the Pleistocene and beginning of the Holocene (interval between 13.0 and 8.5 ka), the Pampean and Patagonian landscape was different from the present one, with a mammal biodiversity larger than in the Middle Holocene; 2) during the Middle Holocene, the highest mammal taxonomic richness corresponds to one species, Lama guanicoe. Although available biomass was the same for the hunter-gatherers, it was due to the larger abundance of individuals of that single species; 3) the emerged continental surface during the Late Pleistocene/Early Holocene was more extensive than during the Middle Holocene. In ecological terms, this greater land mass is reflected in an equally larger biodiversity, even assuming that populations of Pleistocenic megafauna were diminishing in number since ca. 13,500 years BP.Based on the analysis of our own information and published data, we state that the human groups which colonized the Pampean and Patagonian regions towards the end of the Pleistocene and beginning of the Holocene used generalist strategies encompassing a wide range of faunal resources (birds and mammals, especially of terrestrial habitats). Plasticity of hunter-gatherer societies, plus a complex technology, a higher social mobility and unfilled territories, allowed them to rapidly replace one resource for another in conditions of environmental stress. This lifestyle resulted in the occupation of different ecological zones (niches) and the evolution to specialized systems, based on one or a few mammal species, once the colonization and support in the different environments were successful and the resources of the Late Pleistocene/Early Holocene disappeared.  相似文献   

19.
Moraines along the southwestern slopes of the Qilian Shan were dated using cosmogenic radionuclide (CRN) surface exposure techniques to help define the timing of glaciation in northernmost Tibet. The CRN data show glaciers extending 5–10 km beyond their present positions during the global Last Glacial Maximum (LGM) and probably maintained at their maximum extent until the Lateglacial. These data help support the view that glaciers throughout Tibet and the Himalaya were maintained at or near their maximum LGM extent until the Lateglacial. An optically stimulated luminescence date of 11.8 ± 1.0 ka on silt that caps a latero-frontal moraine shows that glaciers had retreated significantly by the end of the Pleistocene and that loess was beginning to form in this region in response to the changing climate during and after the Younger Dryas Stade.  相似文献   

20.
湖南杨二洞更新世晚期动物群研究   总被引:1,自引:0,他引:1       下载免费PDF全文
武仙竹  邓晓  郑利平 《第四纪研究》2008,28(6):1114-1128
湖南花垣县杨二洞化石点位于沅江上游,动物群种类包括有6目26种,动物群时代为晚更新世末期。杨二洞小型哺乳动物化石材料较多。有些小型哺乳动物在我国更新世时期首次发现,如大爪长尾鼩、大黑伏翼、大齿鼠等。杨二洞动物群在我国西南地区更新世末期的材料之中,具有较为突出的森林性特征,反映出湘西北更新世末期具有南亚热带森林古环境。动物群综合研究发现,小家鼠、褐家鼠在中更新世晚期分别产生于中国东北和长江下游,其中小家鼠在更新世晚期经华北向长江流域及其以南扩散,褐家鼠在更新世较晚时期分别向华北和岭南扩散。晚更新世以来,有较多小哺乳动物出现了从低海拔向高海拔山区进行生境转移的现象,这种生境转移对认识大熊猫生态演变有重要参考。杨二洞堆积物特征反映,沅江上游晚更新世末期时河床侵蚀性下切明显,地貌变化显著。  相似文献   

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