A substantial body of research has been accumulated around ammonoids over several decades. A core aspect of this research has been attempts to infer their life mode from analysis of the morphology of their shells and the drag they incur as that shell is pushed through the water. Tools such as Westermann Morphospace have been developed to investigate and scaffold hypotheses about the results of these investigations. We use Computational Fluid Dynamics (CFD) to simulate fluid flow around a suite of 24 theoretical ammonoid morphologies to interrogate systematic variations within this space. Our findings uphold some of the long-standing expectations of drag behavior; conch inflation has the greatest influence over ammonoid drag. However, we also find that other long-standing assumptions, such as oxyconic ammonoids being the best swimmers, are subject to substantial variation and nuance resulting from their morphology that is not accounted for through simple drag assessment.

中文翻译：

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通过系统的形状变化评估菊石壳形状的形态影响

几十年来，围绕类菊酯积累了大量研究成果。这项研究的一个核心方面是试图通过分析它们的贝壳的形态以及当贝壳被推入水中时受到的阻力来推断它们的生活模式。已经开发了诸如 Westermann Morphospace 之类的工具来调查和支持有关这些调查结果的假设。我们使用计算流体动力学 (CFD) 来模拟一套 24 种理论菊石形态周围的流体流动，以研究该空间内的系统变化。我们的研究结果支持了一些长期以来对拖曳行为的期望；海螺膨胀对菊石阻力的影响最大。然而，我们还发现其他长期存在的假设，例如氧锥菊酯是最好的游泳者，