贵州埃迪卡拉纪—寒武纪裂散长索藻Longifuniculum dissolutum的分布及其形态变化

Distribution and Morphological Changes ofLongifuniculum dissolutum from Ediacaran-Cambrian in Guizhou Province,South China

在埃迪卡拉纪-寒武纪地球生命演化和环境变化的重要时期,贵州地区众多后生生物化石群中保存了极为丰富的宏观藻类,这些宏观藻类不仅在早期植物演化中具有极其重要的作用,而且在探索动物与环境协同演化方面也能提供一些重要的信息。文中将分布于贵州埃迪卡拉系陡山沱组-寒武系牛蹄塘组及凯里组的裂散长索藻Longifuniculum dissolutum化石形态进行了详细描述和纵向对比研究,其结果表明自陡山沱组至凯里组沉积期,裂散长索藻的形态变化趋势是藻体逐渐变短变宽,藻丝逐渐变细。这种变化趋势有可能反映L.dissolutum与生态环境变化相适应,也正由于L.dissolutum自身的适应环境的变化使其能够顺利跨过新元古代—寒武纪的重大转折期。从而证实,裂散长索藻L.dissolutum是一类环境适应较强、遗传相对较稳定的一类宏观藻类。

Earth experienced major biological and environmental revolutions during the Precambrian-Cambrian transitional interval, in which the abundant macro-algal were found from the early metzoan biotas in Guizhou Area. The macro-algal not only plays important role in the early evolution of algae plants but also provide some available information in the research of animal evolution and environment change. By means of a longitudinal comparative study, the change trend of the L. dissolutum from Ediacaran to Cambrian was found the thallus became shorter and wider gradually with the filaments tapered off. This diversification may make the thallus adapt to the change of ecological environment from Ediacaran to Cambrian and also allows itself to be survived during the Precambrian-Cambrian transitional interval. The result indicates L. dissolutum is a kind of maroalgae which has wide ecological tolerance and relatively high degree of inherent genetic stability.