Late Paleozoic larval paleobiology and evolutionary dynamics inferred from molluscs of the Buckhorn Asphalt and other lagerstätten

许多重要的古生物问题只能通过分析保存非常完好的化石来解决，比如来自美国俄克拉荷马宾夕法尼亚鹿角沥青的软体动物（尤其是腹足类动物）。这个化石lagerstätte包含到目前为止保存最好的古生代软体动物材料，包括幼虫壳，原始壳矿物学和微观结构。软体动物的壳在很大程度上反映了个体发生的变化。古生代早期个体发生壳（包括幼虫壳）很少保存下来，仅用于分类目的。然而，早期个体发生壳的信息含量要高得多。丰富的腹足类幼虫壳与浮游营养化幼虫发育形成了古代初级生产的代表，即使缺乏浮游植物的直接化石记录，如神秘的晚古生代“浮游植物停电”期间的情况。我们希望量化鹿角沥青和其他特殊保存地点的浮游营养性软体动物物种的比例，作为石炭纪初级生产的证据。这将是重建晚古生代食物网、古群落和古多样性的重要一步。我们意识到，浮游营养型腹足动物的幼虫壳在同一个体中可能与成年壳相似，也可能不相似。因此，我们希望通过比较幼虫和成虫壳的形态空间分析来测试异时性的活性。异时性是讨论最多的进化过程之一，腹足类动物是深入研究这一过程的最佳对象。

Many important paleobiological questions can only be solved by the analysis of exceptionally wellpreserved fossils such as the molluscs (especially gastropods) from the Pennsylvanian Buckhorn Asphalt (Oklahoma, USA). This fossil lagerstätte contains by far the best preserved Paleozoic mollusc material including larval shells, original shell mineralogy and microstructures. Mollusc shells reflect ontogenetic change to a high degree. Paleozoic early ontogenetic shells including larval shells are rarely preserved and have been used for taxonomic purposes only. However, the information content of early ontogenetic shells is much higher. The abundance of gastropod larval shells with planktotrophic larval development forms a proxy for ancient primary production even if direct fossil record of phytoplankton is lacking as is the case during the enigmatic Late Paleozoic ¿Phytoplankton Blackout¿. We want to quantify the proportion of planktotrophic mollusc species from the Buckhorn Asphalt and other sites with exceptional preservation as evidence for primary production during the Carboniferous. This will be an important step towards the reconstruction of Late Paleozoic food webs, paleocommunities, and paleodiversity. We are aware that planktotrophic gastropod larval shells may or may not resemble adult shells within the same individual. Therefore, we want to test the activity of heterochrony through a comparative morphospace analysis of larval and adult shells. Heterochrony is one of the most discussed evolutionary processes and gastropods belong to the best objects to study these processes in deep time.