青藏高原的新生代鱼化石及其古环境意义  

Review of the Cenozoic fossil fishes from the Tibetan Plateau and their bearings on paleoenvironment

作　　者：张弥曼[1] MIAO DeSui 

机构地区：[1]中国科学院古脊椎动物与古人类研究所,中国科学院脊椎动物演化与人类起源重点实验室,北京100044 [2]Biodiversity Institute,University of Kansas

出　　处：《科学通报》2016年第9期981-995,共15页Chinese Science Bulletin

基　　金：中国科学院战略性先导科技专项(B项)(XDB03020104);国家重点基础研究发展计划(2012CB821906);国家自然科学基金(41272028)资助

摘　　要：新生代期间印度-亚洲板块碰撞引起青藏高原快速隆升,将青藏高原转变为与其周边较低地域相隔离的"生态岛".伴随着栖息地被迅速抬升到更高地区的鱼类,积累了适应环境变化的基因和形态特征,演变为新物种.一如加拉帕戈斯群岛之于达尔文,青藏高原同样为我们提供了一个研究"演化进行时"的巨大实验室.此外,由于内陆鱼类局限于内陆水域,其化石亦通常在原地埋藏,而且鱼类的分布严格受水系格局的限制,而水系格局又受地质事件的制约,其系统演化与隆升并进尤为明显.因此鱼化石研究可揭示诸如古气候、古水系格局、古高度等古环境方面的因素,进而协助重建高原隆升的历史.近年来我们在青藏高原发现了非常丰富且保存精良的新生代鱼化石,其中包括裂腹鱼亚科内罕见的全身长有粗骨头的伍氏献文鱼(Hsianwenia wui),它曾生活在含钙极高的特殊盐度的水域中,见证了柴达木盆地的干旱化过程.青藏高原新生代鱼化石的研究显示,有些现在已经相当高的地点,在渐新世、中新世和上新世时仍分别处于很低的地位,而另几个地点在上新世时就已经和现在高度大致相当.我们还推算出,从晚上新世到现代东昆仑的抬升幅度不会超过1000 m.这与目前氧、碳同位素的研究结果(即东昆仑同期曾抬升了2700±1600 m)很不相同,但我们认为化石证据或更可信些.The past two decades have witnessed a renewed vigor in research on geological history of the Tibetan Plateau and the newly emerged paleontological evidence has added a crucial, biological dimension to the scientific quest. Here we review an important part of that paleontological evidence, from fossil fishes, and its implications for interpreting evolutionary history of the plateau. We also provide our thought on the future research directions toward a more holistic approach to the understanding of uplift history of the Tibetan Plateau. The rapid uplift of the Tibetan Plateau, caused by the India-Asia plate collusion, during the late Cenozoic has profoundly influenced the geological, biological, and climatic changes in the region, and changed it into a habitat island isolated from the less elevated surrounding environments. As the fishes, along with their habitats, have been rapidly uplifted, they have kept and accumulated the genetic and morphological traits adaptive to the new environment, evolving into new species. To emulate Charles Darwin＇s ＂descent with modification＂, we have coined ＂ascent with modification＂ to describe this evolutionary pattern of Tibetan fishes. Thus, this makes the Tibetan Plateau a giant laboratory, much like the Galapagos Islands to Darwin, for studying biological evolution ＂in action＂. Moreover, freshwater fishes are usually restricted to the drainages（and their fossils are commonly preserved in situ）, which are in turn constrained by tectonic events, and hence they are ideal candidates in studying biological, geological, and climatic interplays in the ecosystem. The studies of fossil fishes can also reveal many paleoenvironmental proxies such as ancient climate, past drainage patterns, and paleoelevations, helping understand the uplift history of the Tibetan Plateau. In recent years, we have discovered and collected abundant and well-preserved fossil fishes from the Cenozoic strata on the Tibetan Plateau, including Hsianwenia wui, which is an extraordinary thick-bon

关 键 词：青藏高原 新生代鱼化石 古高度 古环境 柴达木盆地 干旱化 

分 类 号：Q915[天文地球—古生物学与地层学]