Molluscan Evolution in the Pannonian Lake (Late Miocene, Hungary)

9706230晚中新世潘尼奥湖是迄今已知的最多样化的特有湖泊软体动物区系之一，包括约1000个已描述的种，数十个特有属，几个特有亚科和两个特有科。尽管这一案例具有教科书性质(例如Stanley 1979-Ager 1963,1993，Sepkoski 1993)，但潘尼奥湖软体动物的进化仅通过对个别谱系的少数研究(例如Geary 1990a-Muller和Magyar 1992a)才知道，但尚未以全面的方式探讨。除了令人印象深刻的软体动物外，潘尼奥湖还为古生物研究提供了一个理想的系统，因为它的古环境和地层学研究得非常好。湖泊古环境和历史的许多方面，包括湖泊的起源、沉积和水深、湖平面波动、古地理和古气候，一直是最近工作的重点。新修订的年代地层学刚刚完成，其中包括详细的生物地层学、地震地层学和磁性地层学数据。国际和平组织的匈牙利合作者Imre Magyar博士和Pal Muller博士是这一知识体系的重要贡献者。我们在这里提出的工作包括几个较小的项目，这些项目将进一步加强我们对古环境的了解。因此，在这一经典系统中，详细研究环境变化与进化变化之间的关系的所有部分都已就绪，我们建议在这一详细的古环境背景下，研究潘尼奥湖软体动物主要分支的进化辐射。我们打算：1)对四个最多样化的软体动物科进行全面的回顾和分类修订，2)使用形态计量学来描述潘尼奥湖部分谱系的地理变异和形态变化，以及3)在环境背景下解释分类和形态结果。具体地说，我们将测试不同软体动物谱系之间的协调、停滞的想法，并研究环境稳定或变化如何影响潘尼奥湖软体动物的多样性和形态进化。地质上的渐变节拍似乎已经在几个潘尼翁盆地软体动物谱系中被记录下来(Geary 1990a；Muller和Magyar 1992a；Staley 1992-Staley等人)。(1992年)。对潘尼奥湖软体动物进化的更全面的认识，包括对其他谱系变化的详细记录，将有助于我们理解各种进化节奏背后的机制。

9706230 Geary The late Miocene Pannonian lake harbored one of the most diverse endemic lacustrine mollusc faunas ever known, including approximately one thousand described species, dozens of endemic genera, several endemic subfamilies, and two endemic families. In spite of the textbook nature of this case (e.g. Stanley 1979- Ager 1963, 1993, Sepkoski 1993), the evolution of the Pannonian lake malacofauna is known only from a few studies of individual lineages (e.g. Geary 1990a- Muller and Magyar 1992a), but has not been approached in a comprehensive way. In addition to its impressive malacofauna, the Pannonian lake presents an ideal system for paleontological research because its paleoenvironment and stratigraphy are extremely well studied. Many aspects of lake paleoenvironment and history, including the origin of the lake, its sedimentation and water depth, lake level fluctuations, paleogeography, and paleoclimate have been the focus of recent work. A newly revised chronostratigraphy has just been completed, which incorporates detailed biostratigraphic, seismic stratigraphic, and magnetostratigraphic data. The PI's Hungarian collaborators, Drs. Imre Magyar and Pal Muller, have been important contributors to this body of knowledge. The work we propose here includes several smaller projects that will further enhance our paleoenvironmental understanding. Thus, all the pieces are in place for a detailed examination of the relationship between environmental and evolutionary change in this classic system, We propose to examine the evolutionary radiation of the major clades of Pannonian lake molluscs in this detailed paleoenvironmental context. We intend to: 1) conduct a comprehensive review and taxonomic revision of four of the most diverse molluscan families, 2) use morphometrics to characterize geographic variation and morphological change over time in selected lineages from the Pannonian lake, and 3) interpret the taxonomic and morphological results in an environmental context. Specifically, we will test the idea of coordinated, stasis among various molluscan lineages, and we will examine how environmental stability or change influenced the diversity and morphological evolution of Pannonian lake molluscs. Geologically gradual tempos appear to have been documented in several Pannonian basin mollusc lineages (Geary 1990a; Muller and Magyar 1992a; Staley 1992- Staley et al. 1992). A more comprehensive view of Pannonian lake molluscan evolution, including detailed documentation of change in additional lineages, will contribute to our understanding of the mechanisms behind various evolutionary tempos.