植食性哺乳动物牙齿磨痕分析方法简介及其在古食性恢复中的应用前景

通过研究古哺乳动物的食性来探讨哺乳动物演化与古生态环境变化之间的关系是目前古生物学研究领域的一个热点,而牙齿磨痕分析是恢复古食性和重建古生态环境的重要手段。牙齿磨痕(dental wear)分析包括微痕(microwear)分析和中痕(mesowear)分析,两种方法均强调食性与牙齿磨痕模式的严格对应,即不同食性的动物具有不同的牙齿磨痕特征模式。近年来,牙齿磨痕分析方法以其简单、快捷和高效等优点已被广泛应用于奇蹄类、偶蹄类、啮齿类、长鼻类和食肉类等哺乳动物的食性研究。但哺乳动物的食性和摄食习性比较复杂,很可能会影响微痕和中痕分析对食性的分辨率。所以,为了获得更加详细的古食性信息和更高的食性分辨率,一方面要对微痕和中痕分析方法进行改进,增添稳定并具有食性识别意义的观测变量,另一方面,需要同时结合微痕和中痕分析,从而获得更加全面的食性信息。虽然牙齿磨痕分析目前主要应用于植食性哺乳动物的食性研究,但其原理对哺乳动物的其它类群也是适用的,随着磨痕分析方法的不断改进和其它类群磨痕数据库的建立,未来的牙齿磨痕分析将可以恢复更多类群的古食性,从而可以更加全面和准确地揭示古食性与古环境信息。

AN INTRODUCTION OF APPLICATION OF DENTAL WEAR ANALYSES IN PALEODIETARY RECONSTRUCTION OF HERBIVOROUS MAMMALS

The dental wear analysis has been widely adopted as one of the key means in reconstructing paleodiet of mammals. It involves microwear analysis and mesowear analysis. Both methods emphasize a strict correlation between diet and dental wear patterns. Namely, mammals with different diet will present different microwear and mesowear patterns on tooth enamel of occlusal surface. In recent years, the simple, convenient, and efficient dental wear analysis has been applied to study the paleodiet of a number of mammalian groups, such as Perissodactyla, Artiodactyla, Rodentia, Proboscidea, and Carnivora, etc. However, dietary and feeding habits of mammals are very complicated, which may obviously affect the resolution of both microwear analysis and mesowear analysis. It is thus necessary to explore and define more microwear and mesowear features indicative to diet reconstruction, which will reveal more detailed paleodietary information and achieve higher resolution. Moreover, the combinational use of both methods can provide more comprehensive data of wear features and will be significantly helpful in reconstructing the diet. Currently, dental wear analysis is mainly applied to study the diet of herbivorous mammals, although its principle is readily extendable to other mammalian taxa. The dental wear analysis in the future will enable the diet reconstruction of more groups with incessant improvement of methods and the establishment of larger wear databases. Therefore, more paleodietary and paleoenvironmental information should be expected to be revealed more accurately and comprehensively by means of dental wear analysis.