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11.
The Middle Stone Age (MSA) layers at Blombos Cave contain abundant bifacial Still Bay points, formal and ad hoc bone artefacts, and an intentionally incised bone piece. These artefacts add weight to arguments that some aspects of modern human behavior developed earlier in sub-Saharan Africa than elsewhere. Four human teeth were recovered from the MSA strata at Blombos during the 1997-1998 excavations. Two are heavily worn deciduous teeth, and two are incomplete permanent premolar crowns. The Blombos di(1)is comparatively large in relation to modern African homologues, falling within the lower part of the observed Neandertal range. The dm(1)and P(3)are comparable to modern teeth and smaller than most Neandertal crowns. The premolars preserve horizontal circum-cervical striae that suggest palliative toothpick use. The di(1)evinces labial scratches that resemble neither the "cutmarks" that have been observed on Neandertal incisors, nor the striae that have been recorded on modern human teeth.  相似文献   
12.
A Late Pleistocene spotted hyena Crocuta crocuta spelaea (Goldfuss 1823) population from the cave bear den Sloup Cave, Moravia (Czech Republic) consists of mainly adult/senior and few cub/juvenile remains and coprolites, and 139 prey bones. Hyenas used the Nicová Cave branch that is connected to the entrance area mainly as a communal den site. Prey bone damage is most visible on the imported woolly rhinoceros remains. The partly excavated prey bone accumulation consists of a single woolly mammoth Mammuthus primigenius (Blumenbach 1799) tooth (2%), mainly Coelodonta antiquitatis (Blumenbach 1807) remains (16%), 4% Bos primigenius (Bojanus 1827) and 1% each of Megaloceros giganteus (Blumenbach 1799) and Rangifer tarandus (Linnaeus 1758). The other carnivores such as Panthera leo spelaea (Goldfuss 1810), Gulo gulo (Linnaeus 1758) and Canis lupus (Linnaeus 1758) subsp. are less represented (1–3%). Wolverines might have been imported also as prey remains, whereas wolves also possibly used this cave on a short-term basis, whereas steppe lions seem to have preyed upon cave bears deeper in the cave periodically, where even skeletons of P. leo spelaea were found in the Elisabeth Cave part.  相似文献   
13.
The lands including Cave Spring and most of northwest Georgia were held by the Cherokee until Cherokee removal in 1838. In 2010, a two-story pine structure that was encased inside the Green Hotel in downtown Cave Spring, Georgia, was revealed during renovation. Local Cave Spring historians insist the log structure was built by Avery Vann in 1810, making it a Cherokee structure. However, the Gold Lottery maps of 1832 show no structure on lot 871, which today contains the Green Hotel. A construction date also cannot be verified by historical documents, maps, or artifacts discovered around the Green Hotel. The purpose of this research was to determine the construction date of the Green Hotel log structure. Archaeological dating of the window glass thickness of the hotel gave dates of 1810 or 1823. However, the dendroarchaeological dating of the wood indicates cutting dates during the late spring/early summer of 1839. This would indicate that the log structure inside the Green Hotel was not built by Avery Vann or any Cherokee, but by later Euro-American settlers.  相似文献   
14.
周口店田园洞古人类化石点的无颈鬃豪猪(Hystrix subcristata)   总被引:6,自引:1,他引:6  
周口店田园洞位于北京猿人遗址西南6km处,是新发现的晚期智人化石地点。该地点是迄今我国北方地区第四纪化石地点中含豪猪材料最丰富的。从头骨、牙齿、头后骨骼的形态特征及大小判断,田园洞的豪猪应归入我国现生无颈鬃豪猪(Hystrixsubcristata)。14C测年表明,含豪猪化石的地层时代为3.05~0.467万年,为更新世末期到全新世中期,是目前所知豪猪化石在我国北方地区的最晚记录。  相似文献   
15.
Systematic excavations carried out since 1989 at Bolomor Cave have led to the recovery of four Pleistocene human fossil remains, consisting of a fibular fragment, two isolated teeth, and a nearly complete adult parietal bone. All of these specimens date to the late Middle and early Late Pleistocene (MIS 7-5e). The fibular fragment shows thick cortical bone, an archaic feature found in non-modern (i.e. non-Homo sapiens) members of the genus Homo. Among the dental remains, the lack of a midtrigonid crest in the M1 represents a departure from the morphology reported for the majority of Neandertal specimens, while the large dimensions and pronounced shoveling of the marginal ridges in the C1 are similar to other European Middle and late Pleistocene fossils. The parietal bone is very thick, with dimensions that generally fall above Neandertal fossils and resemble more closely the Middle Pleistocene Atapuerca (SH) adult specimens. Based on the presence of archaic features, all the fossils from Bolomor are attributed to the Neandertal evolutionary lineage.  相似文献   
16.
The predation pressure of the greater horseshoe bat, Rhinolophus ferrumequinum, on the diapausing population of the noctuid moth, Goniocraspidum preyeri, was examined at an abandoned mine in central Japan. These bats did not prey on the moths in summer. The number of moths preyed on was largest in March. More than 60% of the diapausing moths were eaten by only three or four bats, which accounted for over 90% of all the moth deaths. This moth was an important source of food at the end of the hibernating period when the bat had already used most of its stored subcutaneous fat. The predation on G. preyeri may have raised the overwintering success rate of R. ferrumequinum.  相似文献   
17.
Filamentous microbial mats from three aphotic sulfidic springs in Lower Kane Cave, Wyoming, were assessed with regard to bacterial diversity, community structure, and ecosystem function using a 16S rDNA-based phylogenetic approach combined with elemental content and stable carbon isotope ratio analyses. The most prevalent mat morphotype consisted of white filament bundles, with low C:N ratios (3.5-5.4) and high sulfur content (16.1-51.2%). White filament bundles and two other mat morphotypes had organic carbon isotope values (mean delta13C=-34.7 per thousand, 1sigma=3.6) consistent with chemolithoautotrophic carbon fixation from a dissolved inorganic carbon reservoir (cave water, mean delta13C=-7.4 per thousand for two springs, n=8). Bacterial diversity was low overall in the clone libraries, and the most abundant taxonomic group was affiliated with the "Epsilonproteobacteria" (68%), with other bacterial sequences affiliated with Gammaproteobacteria (12.2%), Betaproteobacteria (11.7%), Deltaproteobacteria (0.8%), and the Acidobacterium (5.6%) and Bacteriodetes/Chlorobi (1.7%) divisions. Six distinct epsilonproteobacterial taxonomic groups were identified from the microbial mats. Epsilonproteobacterial and bacterial group abundances and community structure shifted from the spring orifices downstream, corresponding to changes in dissolved sulfide and oxygen concentrations and metabolic requirements of certain bacterial groups. Most of the clone sequences for epsilonproteobacterial groups were retrieved from areas with high sulfide and low oxygen concentrations, whereas Thiothrix spp. and Thiobacillus spp. had higher retrieved clone abundances where conditions of low sulfide and high oxygen concentrations were measured. Genetic and metabolic diversity among the "Epsilonproteobacteria" maximizes overall cave ecosystem function, and these organisms play a significant role in providing chemolithoautotrophic energy to the otherwise nutrient-poor cave habitat. Our results demonstrate that sulfur cycling supports subsurface ecosystems through chemolithoautotrophy and expand the evolutionary and ecological views of "Epsilonproteobacteria" in terrestrial habitats.  相似文献   
18.
Radon represents the major source of natural radioactivity in confined environments. Despite the clear evidence of a direct association between residential exposure and human lung cancer provided by case-control studies, results relating indoor exposure and genotoxic/mutagenic effect induction are still contradictory. The present study attempts to estimate the genotoxic effects induced by exposure to radioactive radon in wild cricket populations sampled from caves where varying concentrations of radon are present. Cave crickets are also tested as possible bio-indicator organisms of genotoxic potential of contaminated residential and confined environments. Six caves in Central Italy are considered covering a broad spectrum of radon radioactivity concentration (221-26,000 Bq/m3). Dolichopoda specimens were sampled from each cave; both haemocytes and brain cells taken from individuals were tested for responsiveness to DNA damage induced by radon through the Comet assay. Specimens from the least radioactive cave, housed in controlled conditions for 60 days before analysis, were used as control group. Statistically significant increase of DNA damage was found in all groups of individuals from each cave, for both cell types. Very low values of all Comet parameters were found in control group individuals, which gave indications of a good responsiveness of the organism to the variable environmental levels of radioactive contamination. Results indicate that cave crickets represent a reliable tool for the detection of genotoxic potential induced by radioactive contamination of confined environments and can be proposed as a possible bio-indicator system for air (-radioactive) pollution related to indoor exposure [Current Zoology 60 (2): 299-307, 2014].  相似文献   
19.
我国丰富的古人类遗存为研究东亚乃至全球古人类起源、迁徙和演化提供了重要的基础材料与数据。对已发表的2000多处旧石器时代古人类遗址年代学数据的整理和统计分析发现,绝大多数遗址目前仍缺少基本的年代学数据,不足20%的遗址开展过测年,仅10%左右具有相对可靠的年代学数据,只有极少数开展了多种测年方法的交叉定年。对于80多处出土古人类化石的遗址,亦过半存在明显的年代学争议。我们对一些古人类遗址中的常见各种复杂的同沉积和沉积后改造现象进行了详细分析,探讨了我国测年平台和测年队伍建设、考古发掘以及年代学采样与测年方法学等方面存在的问题,及其对遗址年代学研究的可能影响。基于此,笔者提出改善我国古人类年代学研究现状的可能措施,希望可以抛砖引玉,引发对该研究领域更多的关注和思考。  相似文献   
20.
山顶洞人化石是迄今在东亚地区发现的数量最为丰富、保存状态最为完好的更新世晚期人类化石。多年来,山顶洞人作为东亚地区更新世晚期人类的代表,在研究东亚地区现代蒙古人种及美洲印第安人起源方面发挥着重要作用。随着对现代人起源与演化研究的深入,学术界对更新世晚期人类演化及现代人群形成过程的许多细节及演化机制予以了越来越多的注意,提出了现代人群出现时间及现代人群分化时间的概念。一些研究对山顶洞人的演化程度及其在东亚地区现代人群形成上的作用也提出了不同看法。为了深入探讨这些问题,本文对12项颅骨非测量特征在山顶洞人与现代中国人的表现情况进行了对比研究。发现有8项特征在山顶洞人与现代中国人之间具有不同的表现,作者认为山顶洞人在颅骨特征表现上较现代中国人具有更多的原始性。在此基础上,作者就更新世晚期人群内部变异、现代人群特征标准等问题进行了讨论。  相似文献   
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