COLLABORATIVE RESEARCH: Soft Tissue Preservation in Permian Cephalopods

我们计划研究北美二叠纪沉积物中头足类软体动物的内部特征。特别是，我们正在研究内华达州巴克山二叠纪头足类动物早期成岩磷矿化保存的虹管索和膜软组织遗骸。这项研究代表了我们在这个地方的三个氨类标本中最初发现的保存膜的后续研究。我们计划扩展这一发现，我们的主要目标是检查巴克山头足类动物群保存的膜和软组织。该动物群包括prolecanides， gongonatiids和nautiloides，被安置在俄亥俄大学和博伊西州立大学。我们将使用酸化技术制备这些头足类动物，然后用扫描电子显微镜检查标本。对古生代头足类动物软组织和膜残体的研究一直是一个无法实现的研究目标。我们提出了两个假设：1)这些头足类动物的结构确实是软组织的残骸，现在被磷化，保留了它们原始微观解剖的细节；2)这些结构与现代头足类动物的结构是同源的，并揭示了系统发育和功能形态学的信息。这项研究将使人们更好地了解这些古老的、已经灭绝的动物是如何在它们的环境中生活和发挥作用的。通过这种方式，这些发现将有助于我们对头足类化石的古生物学基础知识。

We plan to investigate the internal features of cephalopod molluscs from Permian deposits in North America. In particular, we are studying the remains of soft tissues of siphuncular cords and membranes that have been preserved by early diagenetic phosphate mineralization in Permian cephalopods from Buck Mountain, Nevada. This research represents a follow-up study of our initial discovery of preserved membranes in three ammonoid specimens from this locality. We plan to expand this discovery with our primary objective the examination of the Buck Mountain cephalopod fauna for preserved membranes and soft tissues. This fauna includes prolecanitids, goniatitids, and nautiloids and is housed in Ohio University and Boise State University. We will prepare these cephalopods using acidification techniques and then examine the specimens with scanning electron microscopy. The study of the remains of soft tissues and membranes in Paleozoic cephalopods has previously been an unobtainable research goal. We pose two hypotheses: 1) the structures in these cephalopods are, indeed, soft tissue remains, now phosphatized, that preserve the details of their original microanatomy and 2) that these structures are homologous with those of modern cephalopods and reveal information about phylogeny and functional morphology. This study will lead to a better understanding of how these ancient and extinct animals lived and functioned in their environment. In this way, these discoveries will contribute to our fundamental knowledge of the paleobiology of fossil cephalopods.