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河北省秦皇岛灵仙洞发现了一批最后斑鬣狗化石,标本达上千件,至少代表了30个不同个体,包括3具骨架(其中骨架Ⅰ是世界上迄今所发现最完整的1具),还发现了一些其他哺乳动物化石,共计26属27种.根据动物群组成、地质地貌以及堆积物的综合分析判断,它的时代可能属于中更新世晚期至晚更新世早期.动物群的生态组合反映当时处于一个温热偏干、半封闭或开阔的山间草原而周边山上有树林的生态环境.标本(尤其是完整骨架)的保存为典型的原地埋藏,死后未受到包括斑鬣狗自身在内的动物干扰和破坏.斑鬣狗在动物群中占绝对优势以及幼年个体和粪化石的发现,表明灵仙洞是一处斑鬣狗族群的巢穴.与其他斑鬣狗巢穴不同的是:斑鬣狗的猎物稀少,鲜见斑鬣狗的活动痕迹,尤其是幼年斑鬣狗啃咬形成的特定产物“nibbling sticks”,这说明灵仙洞既非用于猎物遗骸的储藏,也非用于幼崽的抚养,而是一处共用巢穴,同时也表明灵仙洞的骨骼聚集与埋藏有着特定的成因和机理.  相似文献   
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孙启高 《地质论评》2008,54(2):145-154
古海拔问题是当前古植物学与古环境研究领域中的难点之一,属于化石植物生物学与地球科学和环境科学相互交叉、相互渗透的前沿性研究。定量研究古海拔的变化对阐述诸如青藏高原抬升历史等重大科学问题具有十分重要的意义。应用生物学的思想和方法,利用化石植物研究地质历史时期古海拔的变化是当前研究的一个热点。化石植物既是研究地质历史时期植被演替的直接证据,又是研究古海拔变化的珍贵材料。本文简述了利用化石植物定量研究古海拔的3类主要方法,即最近亲缘种分析、共存因子分析和叶相分析的基本原理和实际应用,侧重分析中国地区(如西藏南部南木林盆地)古海拔的研究进展和存在问题,并结合近年来的研究实践展望了将来的工作。  相似文献   
3.
孙启高 《地质论评》2009,55(4):605-608
1 科学术语的意义及术语"活化石" 众所周知,术语问题是科学研究中不可回避的基本问题.笔者认为,科学术语属于学科自身发展过程中各个历史阶段的研究成果,是构成人类科学体系的知识内容,是丰富人类语言文化的重要来源.  相似文献   
4.
???????μ???????????????????????????Kalman???????Rauch??Tung??Streibel (RTS)??????????????????????????????????????????Kalman???????????????????????????????????÷???????????????????????????????????и???????????????GPS/DR?????????????飬?????÷???????Ч???  相似文献   
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The first unequivocal remains of medium to large-sized mustelids from the middle Miocene Halamagai and Kekemaideng formations have been found in the Ulungur River area, Xinjiang, northwestern China. These new fossils are referred to the hypercarnivorous mustelid Hoplictis Ginsburg, 1961 and denote the first record of the genus in East Asia.We define Hoplictis baihu n. sp., for the mustelid from Tieersihabahe(Halamagai Fm.), which represents the smallest species of the genus. This primitive form is closer to H. florancei and H. noueli than to H. anatolicus and later, larger and more derived Hoplictis spp., from Europe and North America. A large toothless mandible from Duolebulejin(Kekemaiden Fm.) is assigned to Hoplictis cf. helbingi, and it presumably might represent the first record of H. helbingi outside Western Europe. The systematic position of Hoplicitis in relation to Ischyrictis with which it is similar is clarified. The occurrence in East Asia of two species of Hoplictis greatly expands the known distribution and diversity of the genus, and supports a Palaearctic Neogene dispersal event of carnivorans between Europe and Asia during the late Shanwangian–early Tunggurian equivalent to MN5–6 in Europe, and indication of another dispersal event from Europe to North America,through Northwest China during the late Tunggurian, equivalent to MN7–8 in Europe.  相似文献   
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Felid material from the middle Early Pleistocene Haro River quarry, northern Pakistan, is described. Most of the material is referred to the Eurasian jaguar, Panthera gombaszogensis georgica, representing the first record of the jaguar in southern Asia. A systematic review of dental morphology of all living species of Pantherinae is made to provide a better background for studying the evolution of pantherine cats. A renewed dispersal scenario of the jaguar in Eurasia is provided. Panthera gombaszogensis georgica is suggested to be a distinct subspecies distributed in central, western and southern Asia during the Early Pleistocene, characterized by relatively small body size and slender dentition. The Eurasian jaguar does not possess the derived dental characters of the living jaguar Panthera onca (e.g. weak or no canine vertical groove, robust premolars), and presumably did not specialize on hard-shelled prey, and therefore should be viewed as a distinct species from the living P. onca. Two additional felids from the Haro River Quarry, the large sabre-toothed felid? Megantereon sp. and a small undetermined feline, are also reported. The Felidae faunal composition of southern Asia during the Early Pleistocene is generally similar to that of northern Eurasia, and the paleoenvironment is probably slightly more closed.  相似文献   
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