河北秦皇岛斑鬣狗巢穴（灵仙洞）及斑鬣狗的集群死亡与埋藏

MASS MORTALITY OF A LARGE POPULATION OF THE SPOTTED HYENAS （CROCUTA ULTIMA） AT THE LINGXIANDONG CAVE, QINHUANGDAO,HEBEI PROVINCE： A HYENA COMMUNAL DEN WITH ITS PALAEOECOLOGICAL AND TAPHONOMICAL INTERPRETATION

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.

The Lingxiandong Cave（40°12＇08.58＂N,119°33＇46.63＂E）is approximately 1.1 km north of the Banchangyu Village of Funing County,Hebei Province,and located 30 km north of Qinhuangdao and 15 km to the northeast of Shanyangzhai of another fossil site.It is a newly discovered fossil site from which a large number of fossil remains of Crocuta ultima were unearthed with excellent preservations.The specimens of the spotted hyena collected from the cave could amount to thousands of pieces,which represent 30 different individuals at least,including 3 complete or part skeletons.Moreover,the skeleton I is the most complete one ever found all over the world so far,which is also one of the most spectacular discoveries from the cave.In addition to the hyenas,a number of other mammalian remains,a total of 26 genera and 27 species,were unearthed successfully from the cave.The comprehensive analysis of the multi-disciplinary data,such as Quaternary neotectonics,landform evolution,karst geomorphy,deposit and fauna compositions and so on,indicates that it may be in the late Middle Pleistocene to early Late Pleistocene,during a period of a little warmer but drier than today,with an ecological landscape of semi-closed or open grasslands between the wooded mountains.The fantastic preservation of the bones（especially the complete skeletons）implies a typical autochthonous deposit,and also manifests that the spotted hyenas were buried after the death so quickly that no further postmortal disturbance or damage was imposed by other animals including hyenas themselves.The spotted hyena is a dominant species of the fauna,of which the individual number is about 69.8% of total members of the fauna（except the small mammals）.The population of hyena is mainly composed of adult individuals,roughly 83.3%,which outnumbers most Pleistocene hyena dens of the whole world.The high amount of hyena bone accumulation indicates undoubtedly that the cave is a hyena den.Moreover,the discovery of cub and juvenile individuals and hyena coprolites as well,also presents other arguments for the identification of a hyena den.However,as a hyena cave den,the Lingxiandong Cave is different from other hyena den sites in small amount of prey bones and no distinctive signs of hyena activity such as cracking,chewing and gnawing marks.Especially no nibbling sticks,a special bone fragment intensively gnawed and chewed by the cubs or juveniles of hyena,was discovered at all from the cave.All these arguments mentioned above demonstrate that the cave is neither a prey depot den,nor a cub-raising den,but a communal den,and that the bone accumulations and the taphonomy of hyenas in the cave are of specific causes and mechanism.