北京房山十渡及霞云岭晚更新世岩羊（Pseudois nayaur）化石

IVPP-IR > 硕博论文

	北京房山十渡及霞云岭晚更新世岩羊（Pseudois nayaur）化石
其他题名	LATE PLEISTOCENE PSEUDOIS NAYAUR FROM THE XITAIPING CAVE, SHIDU AND XIAYUNLING
	许治军
学位类型	硕士
导师	同号文
	2009-06-05
学位授予单位	中国科学院古脊椎动物与古人类研究所
学位授予地点	古脊椎动物与古人类研究所
关键词	岩羊房山十渡霞云岭晚更新世
摘要	岩羊（Pseudois nayaur）是中亚地区特有属种，现生种类主要分布在我国青藏高原及其周边和黄土高原等地，在喜马拉雅山脉南坡也有分布。目前对岩羊的研究多立足于生态学和分子生物学等方面，其骨骼特征的研究甚少。长期以来，晚更新世以来的岩羊化石发现较少，材料零散，空间分布不连续。幸而近年来在北京周边山区，比较集中地发现了晚更新世化石岩羊。特别是2005年发掘的十渡西太平洞及与其一山之隔的霞云岭，出土了大量岩羊化石，经AMS 14C测年确定西太平洞动物群年代为距今29335～37350年，霞云岭化石材料的年代为距今23185～35030 年，时代均为晚更新世晚期。本论文以这两个地点的化石材料为基础（包括17件残破头部，4件残破下颌骨，102颗牙齿以及143件头后骨骼），系统记述化石岩羊骨骼特征和测量数据并对比现生岩羊的骨骼特征和测量数据，认为该批化石具有与现生岩羊Pseudois nayaur一致的特征，如：颅骨呈四面形锥体，面部较长；前颌骨体向外侧膨出明显，前颌骨鼻突与鼻骨接触；面结节圆隆发育；泪骨无泪凹；额面平且雌性略有凹陷；眼眶圆向外侧延伸；额骨弯曲处位于两角心之间的中间位置，脑颅部与枕面形成极大的夹角，几乎形成同一平面；枕嵴粗糙呈“M”形；副枕突窄扁，向内侧弯曲；角心粗大，向上分散弯曲，略向外旋转, 内侧及后侧面有明显的棱等。应归属于Pseudois nayaur种。进一步对现生岩羊骨骼标本（3个雄性岩羊头骨、3个雌性岩羊头骨，以及一雌一雄完整骨架）进行了系统观察与测量，尝试建立岩羊化石的鉴定依据。在对比了化石岩羊与现生岩羊各部位骨骼测量数据之后，认为晚更新世晚期以来其体格可能存在着逐渐变大的趋势。并据此对已报道的化石岩羊地点进行了材料核实，认为河北宣化、辽宁喀左鸽子洞、上方山云水洞、北京门头沟牛眼洞、榆林火石梁遗址的化石材料均可确定无疑地归入Pseudois nayaur种；辽宁朝阳龙城马山洞发现的岩羊（未定种）由于角基横径与纵径及角心长度与此次研究的雌性岩羊标本相差较大，暂不能确定其具体分类位置。对Pseudois nayaur与相近属种Capra hirus和Ovis aries头骨测量数据进行聚类分析后，认为Pseudois nayaur与Capra hirus头骨的相似度较其与Ovis aries的更高。总结了岩羊的地理和地史分布，认为晚更新世以来岩羊主要分布于我国东北和华北地区，生活环境始终为丘陵、山地或高原。岩羊由晚更新世至今似忽存在对生境的选择和大范围的迁徙，但这一推断尚需更多的化石证据。
其他摘要	The Bharal or blue sheep (Pseudois nayaur) is an endemic species in central Asia. It is widely distributed in the northwest provinces and the Tibetan Plateau of China, and the south slope of the Himalaya Mountain. As an endangered species, recent years many researches were carried out on its physiological and ecological features, and molecular biology. By contraries, there were few studies focused on the skeleton morphology of blue sheep. For a long time there were only a few sites with fossil blue sheep whose materials are very poor and distributions are very limited. It was fortunate that the most abundant fossils of blue sheep were found in Xitaiping Cave of Shidu recovered in 2005 and in Simatai of Xiayunling, another cave in the vicinity, in the southwest suburb of Beijing. By AMS 14C dating, the age of the mammalian fauna from Xitaiping Cave was determined to be 29335～37350 yr BP, the fossils from Xiayunling to be 23185～35030 yr BP, both correlated to the late Late Pleistocene. Fossils of blue sheep from Xitaiping Cave and Xiayunling were studied in this dissertation, including 17 broken bones from the skull, 4 broken mandibles, 102 teeth and 143 postcranials. Based on morphological description and measurements, and comparison with recent blue sheep，these fossils were considered to have the same features as recent Pseudois nayaur in the following features: cranium is quadrangles pyramid, with long rostrum; premaxillary body expanded at distal end, and connected proximally with nasal bone; facial tubercle rounded and robust; without lacrimal pit; frontal flat or slightly depressed in the female; orbits are rounded and extend outward; the bending point of the frontal lies at the level between the horncores; the angle between the parietal and occipital is very large, nearly 180º; occipital crest rough and “M” shaped from posterior view; paroccipital process narrow and flat, extending inward; horncore robust, extending upward and outward, and slightly spiraling outward, with rough striae on the inner and posterior faces etc. Therefore, they can be identified as the species Pseudois nayaur. The identification items for the skeleton of Pseudois nayaur were summarized on the basis of observation and measurements on 3 skulls from extant male individuals, 3 skulls from females, and two complete skeletons of both male and female. Then the rejudgement on the reported fossil blue sheep was carried out. The results showed that the identification work were correct in most fossil site such as Xuanhua in Hebei, Gezi Cave of Kazuo in Liaoning, Yunshui Cave in Beijing, Niuyan Cave in Beijing, and Huoshiliang site of Yulin, except Pseudois sp. from Mashandong in Liaoning, which was not verified due to lack of identifiable parts. Through the comparisons on the sizes of both fossil and extant Pseudois nayaur, it seems that the blue sheep shows a tendency of gradually increasing in body size since the late Late Pleistocene onward. Furthermore, the cluster analysis on data from the measurements on skulls of Pseudois nayaur, Capra hirus and Ovis aries demonstrated that the blue sheep was more closely related to Capra than to Ovis in respect of morphological similarity. The distribution of the blue sheep in the past showed that their distribution range retreated from the northeastern China and mountainous area of North China to the southwestern and northwestern China. Whether the long distance migration of blue sheep since late Late Pleistocene exists or not is still in need of more fossil evidences.
页数	80
语种	中文
文献类型	学位论文
条目标识符	http://119.78.100.205/handle/311034/1702
专题	硕博论文
推荐引用方式 GB/T 7714	许治军. 北京房山十渡及霞云岭晚更新世岩羊（Pseudois nayaur）化石[D]. 古脊椎动物与古人类研究所. 中国科学院古脊椎动物与古人类研究所,2009.

条目包含的文件
文件名称/大小	文献类型	版本类型	开放类型	使用许可
10001_20052800541400（1650KB）			开放获取	--	请求全文