腕足动物数据库及定量古生物地理学研究——以全球二叠纪Roadian-Wordian期为例

ROADIAN-WORDIAN (PERMIAN) GLOBAL BRACHIOPOD DATABASE AND QUANTITATIVE PALAEOBIOGEOGRAPHIC ANALYSIS

随着古生物原始资料的不断积累,通过建立数据库对化石资料进行搜集和管理已成为一种趋势。丰富的原始数据,使我们进行古生物地理研究,特别是大尺度定量古生物地理研究成为可能。文章从化石数据库的建立开始,详细地介绍一种古生物地理学定量研究的方法。通过对二叠纪Roadian-Wordian期全球381个腕足动物属分布数据的聚类分析,区分出4个腕足动物生物域(北方域、冈瓦纳域、泛大洋域、古赤道域)和9个生物区[东北欧区(Northeast European)、维尔科累马区(Verkolyma)、格兰丁区(Grandian)、华夏区(Cathaysian)、基墨里区(Cim-merian)]、中蒙日区(Sino-Mongolian-Japanese)、泛大洋区(Panthalassan)、西澳区(Westralian)和澳纽区(Aus-trazean),这4个域和9个区的生物地理区系特征与它们当时的古地理位置基本吻合。同时,多维尺度分析表明,与纬度相关的温度梯度是控制腕足动物分布的主要因素,古地理屏障和洋流可能在腕足动物空间分布模式的形成中同样扮演着重要角色。

Recently, there has been an increasing use of quantitative, computer-based methods in analyzing the spatial and temporal distributions of different fossil groups. Abundantly published palaeontological data enable us to study palaeobiogeography quantitatively. This paper provides an introduction of fossil database building and methodology of quantitative palaeobiogeographical study using the Roadian-Wordian （Middle Permian） global brachiopod database as an example. Based on the results of the analysis, four realms and nine provinces can be recognized during the Roadian-Wordian stages. They are the Boreal, Palaeoequatorial, Panthalassan and Gondwanan realms. The nine provinces are the northeastern European, Verkolyma, Grandian, Cathaysian, Cimmerian, Sino-Mongolian-Japanese, Panthalassan, Westralian and Austrazean provinces. Nonmetric multidimensional scaling analysis reveals that latitude-related thermal gradient is the major control factor, and palaeogeographic barrier and oceanic currents also played an important role in determining the spatial distribution of Permian brachiopods.