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1.
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 A construction date also cannot be verified by historical documents, maps, or artifacts discovered around the Green Hotel.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   
2.
The troglobitic amphipod crustacean Crangonyx antennatus occupies mud-bottom pools and small, gravel-bottom streams in caves in the southern Appalachians. One large, mud-bottom pool population in Lee Co., Virginia was observed periodically from 1967 to 1975. Amphipods in this population frequently burrowed into the soft mud substrate, where they were able to survive desiccation during periods when the pool dried up. Animals kept in the laboratory also burrowed and survived desiccation during an experiment which simulated drought conditions similar to those observed in caves. Amphipods collected from both pool and stream habitats burrowed, thereby indicating that stream-adapted populations of this species still retain sufficient flexibility to survive under variable environmental conditions that might be encountered in nature. It is concluded that burrowing provides a means of survival for C. antennatus when it is sometimes exposed to drought conditions in cave pool habitats and also provides protection from potential terrestrial predators under similar conditions. Burrowing also offers amphipods protection from aquatic predators (such as salamander larvae) during normal water levels and possibly allows juveniles a means of escaping cannibalism by adults.  相似文献   
3.
Caves are oligotrophic, dark and less-explored environments and are considered as sources of promising microbial strains in biotechnology. Hampoeil Cave is located in massive dolomite with thin bedded limestone in northwestern of Iran. In an isolation and screening program, various samples from soil, water, floor, wall and ceiling of Hampoeil cave and its invertebrates were collected. Four various treatments and 10 different isolation media were used for the isolation of the actinobacteria. Screening of the isolates for antimicrobial activity against 10 bacteria and fungi, 5 hydrolytic enzymes production and resistance to 5 heavy metals have been performed. Among 33 various samples, 76 actinobacteria from various genera, including Streptomyces, Micromonospora, Micrococcus, Kocuria and Corynebacterium were isolated. Eighty percent of the strains had one of the studied hydrolytic enzyme activity. At least one type of antimicrobial activity was seen in 25.3% of the isolates. Resistance to one metal or more was seen in 26.32% of the isolates. The ratio of rare-actinobacteria in the oligotrophic samples to enriched samples is 20% more than Streptomyces. Percentage of strains with the highest activity in esterase, amylase, DNase, protease or lipase activity that were isolated from organic-rich environmental samples were 100, 100, 100, 82 and 82%, respectively. Also, 26.32% of the actinobacterial isolates resisted to heavy metals. It was concluded that Hampoeil cave is a good source in finding cave-living actinobacteria potent in producing hydrolytic enzymes and bioremediation.  相似文献   
4.
This paper examines spatial patterning and settlement dynamics of early Middle Paleolithic hominins at Douara Cave, located on the northern edge of the Syrian Desert. The analyzed material came from our 1984 excavations of Horizons IVB–IVD, techno-typologically assigned to the Tabun D-type Levantine Mousterian (ca. 250 to 130 ka). Two findings are reported. One is the existence of spatial organization in the cave interior. Analysis of the field records shows that the occupation floor of the early Middle Paleolithic at Douara was well-organized into specific activity areas with a focal area of intensive activities close to the back wall. This suggests that the organized use of space known at late Middle Paleolithic sites like Tor Faraj, Jordan, is also applicable to the early Middle Paleolithic. Second, this paper discusses the functional role of this cave within the regional settlement system. A range of features characterizing its living floor(s) point to a very low occupational intensity, undoubtedly reflecting adaptation and particular land use patterns in the arid environments of this region. Moreover, this pattern, along with the division of interior space, seems to have remained consistent through multiple early Middle Paleolithic levels (IVB–IVD). These observations suggest that Douara Cave was a short-term camp embedded in a regional settlement system in the arid environments of this period.  相似文献   
5.
Emerging diseases and expanding carnivore populations may have profound implications for ungulate harvest management and population regulation. To better understand effects of chronic wasting disease (CWD) and cougar (Puma concolor) predation, we studied mortality and recruitment of elk (Cervus elaphus) at Wind Cave National Park (WICA) during 2005–2009. We marked 202 elk (83 subadult M and 119 subadult and ad F) with Global Positioning System (GPS) collars, observed 28 deaths during 74,220 days of monitoring, and investigated 42 additional deaths of unmarked elk found dead. Survival rates were similar for males and females and averaged 0.863 (SE = 0.025) annually. Leading causes of mortality included hunting (0.065, SE = 0.019), CWD (0.034, SE = 0.012), and cougar predation (0.029, SE = 0.012). Marked elk killed by hunters and cougars typically were in good physical condition and not infected with CWD. Effects of mortality on population growth were exacerbated by low rates of pregnancy (subadults = 9.5%, SE = 6.6%; ad = 76.9%, SE = 4.2%) and perinatal survival (0.49, SE = 0.085 from 1 Feb to 1 Sep). Chronic wasting disease, increased predation, and reduced recruitment reduced the rate of increase for elk at WICA to approximately λ = 1.00 (SE = 0.027) during the past decade. Lower rates of increase are mitigating effects of elk on park vegetation, other wildlife, and neighboring lands and will facilitate population control, but may reduce opportunities for elk hunting outside the park. © 2011 The Wildlife Society  相似文献   
6.
古DNA捕获技术目前已获得极大的发展,能够从骨骼和环境沉积物等多种材料中获取到目的DNA片段,而且对于保存环境较差的低纬度地区,同样能够获取有效的内源DNA片段,极大地丰富了古DNA研究的材料来源。本文围绕这一新技术开展总结和讨论,主要分为两个方面:1)总结并介绍该技术应用前景;2)应用这一技术打开了中国南方早期人群研究的新局面,梳理该新技术的应用对史前中国南方人群古基因组研究所获得的新认识,并对中国南方早期人群古基因组深入分析;另外,利用古DNA捕获技术成功获取云南3446~3180 BP的大阴洞遗址4例高质量线粒体基因组信息,并开展了人群遗传历史的研究。  相似文献   
7.
湖北郧西白龙洞古人类遗址初步研究   总被引:4,自引:1,他引:3  
湖北省郧西县白龙洞遗址经过两次正式发掘,出土了古人类牙齿化石、石制品、骨制品等文化遗物和大量动物化石,是一处重要的古人类遗址.2007年4-5月,作者在该遗址周围进行了地质、地貌调查,并对以往发掘出土的部分动物化石和文化遗物进行了整理.同年9月,作者在白龙洞进行探察和小规模试掘,出土大量动物化石和少量石制品、骨制品等文化遗物.同时还发现可疑燃烧痕迹、动物骨骼表面痕迹以及特殊的动物化石埋藏现象等古人类活动证据.白龙洞发育于上新世沙坪组砾岩、泥晶灰岩和泥灰岩地层中,近水平状节理和裂隙为洞穴发育提供前提条件,垂直渗流为溶蚀的主要方式.白龙洞遗址属原地埋藏,动物群的组合显示中更新世早期的面貌,石英岩岩脉原料可能是导致石器工业组合显示北方石器工业面貌的原因.对遗址分布及埋藏现象的初步分析显示,白龙洞为一处多功能的古人类活动遗址.  相似文献   
8.
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   
9.
广西柳城巨猿洞是迄今我国所发现的含爪兽化石最丰富的第四纪化石点。该化石点的爪兽上颊齿原尖强壮,呈圆锥状;次尖发育,呈新月形;原脊完全退失;m3齿带更发育;可归入我国第四纪较常见的中国黄昏爪兽(Hesperotherium sinense)。但柳城巨猿洞的标本明显比我国其他第四纪地点的爪兽较小,尤其是比早更新世晚期的代表小很多。在形态特征方面,柳城巨猿洞的爪兽与重庆巫山的最为接近,而与安徽繁昌及湖北建始的差异较大;但在牙齿的宽/长比值方面,却与安徽繁昌的最为接近。我国已发现的爪兽化石以单个牙齿为主,在分类鉴定方面存在诸多问题,通过牙齿测量的点散布图,可以有效地检验对零散爪兽牙齿齿序的鉴别是否正确。  相似文献   
10.
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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