猛犸象－披毛犀动物群起源与演化研究

The Mammuthus-Coelodonta faunal complex is the largest terrestrial mammalian fauna on the earth during Late Pleistocene, whose principal components are woolly mammoth (Mammuthus), woolly rhino (Coelodonta) and bison (Bison). Although the recent discoveries and studies revealed that the remote ancestors of woolly rhino and woolly mammoth may have originated in China, the details of origin and evolution of these animals are far from clear because of the long age hiatus and poor fossil materials. The current project aims at the studies on the close ancestors of true woolly mammoth, true woolly rhino and bison. The fossils going to be studied are from Early Pleistocene strata in Nihewan Basin in Hebei Province and Gonghe Basin in Qinghai Province. The comparative specimens are from the Late Pleistocene strata in Northeast China. The major work of the project includes the studies on the fossils unearthed and searching for new fossils. The study is going to focus on the morphological studies, including observing (by conventional method, CT scanning and 3D reconstruction), measuring, describing, cladistic analysing and comparing etc. The definite goal is to reconstruct the evolutionary lineages of Mammuthus, Coelodonta and Bison respectively. In addition, the paleoenvironment will also be inferred based on the analysis of faunal compositions.

猛犸象－披毛犀动物群是晚更新世期间在地球上分布范围最广的陆地哺乳动物群；猛犸象、披毛犀和野牛是构成该动物群的骨干成员；但其起源问题却一直未彻底搞清。虽说近年的发现与研究认为草原猛犸象和披毛犀远祖均起源于我国，但由于时代间隔太长或化石材料所限，对这些祖先类型的生物学特性及演化的中间环节还知之甚少。本项目将重点研究与真猛犸象、真披毛犀和野牛更为接近的祖先，研究材料主要来自河北省泥河湾和青海省共和盆地的早更新世地层，上述地点已发现大量早期猛犸象、披毛犀及野牛化石；参考标本是来自东北地区晚更新世地层的有关化石。工作内容是对近年来已发现化石的研究，并开展新的野外调查和化石发掘；研究重点是形态学，包括对化石的观察（常规方法、CT扫描及3D重建）、测量、描述、性状分析和比较等；目的是建立猛犸象、披毛犀和野牛这3大类群各自的演化谱系。此外，从整个动物群组成来进行古生态分析，进而推断动物群演化的古环境问题。

猛犸象－披毛犀动物群是中-晚更新世期间在欧亚大陆中高纬度地区广泛存在的动物群，其组成稳定、分布广泛，是进行区域对比的重要动物群；但长期以来，该动物群的起源和演化问题未得到专门研究。10多年前，在泥河湾盆地发现了该动物群早期代表的化石，依托本项目，又进一步对该化石点进行了发掘和研究；目前已发现哺乳动物化石千余件，并分别对猛犸象－披毛犀动物群的早期类型的化石进行了专门研究，包括草原猛犸象、泥河湾披毛犀、古中华野牛、直隶狼、板齿犀及真枝角鹿等，其中前3个属种代表了猛犸象－披毛犀动物群中3个最重要成员的直接祖先。本项研究表明，泥河湾盆地是猛犸象-披毛犀动物群起源和演化的重要地区，因为在早更新世期间，该动物群的3个最重要成员（真猛犸象、真披毛犀和草原野牛）的祖先类型在泥河湾盆地都同时出现。