Dataset to: Páll-Gergely et al. (2024): "Many roads to success: Alternative routes to building an economic shell in land snails"

<p>3D models based on microCT scans of snail shells. This is the dataset to the publication "Many roads to success: Alternative routes to building an economic shell in land snails" (2024) by Páll-Gergely et al.:</p><p>Land snails exhibit an extraordinary variety of shell shapes. The way shells are constructed underlie biological and mechanical constraints that vary across gastropod clades. Here, we quantify shell geometry of the two largest groups, Stylommatophora and Cyclophoroidea, to assess the potential causes for variation in shell shape and its relative frequency. Based on μCT scans, we estimate material efficiency through 2D- and 3D-generalisations of the isoperimetric ratio, quantifying the ratios between area and perimeter of whorl cross-sections (2D) and shell volume and surface (3D), respectively. We find that stylommatophorans optimise material usage through whorl overlap, which may have promoted the diversification of flat-shelled species. Cyclophoroids are bound to a circular cross-section because of their operculum; flat shells are comparatively rare. Both groups show similar solutions for tall shells, where local geometry has a smaller effect because of the double overlap between previous and current whorls. Our results suggest that material efficiency is a driving factor in the selection of shell geometry. Essentially, the evolutionary success of Stylommatophora likely roots in their higher flexibility to produce an economic shell.</p>

<p>基于蜗牛壳的微CT扫描的3D模型。此数据集为Páll-Gergely等人于2024年发表的论文《许多通往成功的道路：陆生蜗牛构建经济型壳的替代途径》的配套数据集：</p><p>陆生蜗牛展现出壳形多样的非凡特性。壳的构造方式受到生物和机械限制，这些限制在不同腹足纲类别中各不相同。在本研究中，我们对两个最大的类群，即Stylommatophora和Cyclophoroidea的壳几何形状进行了量化分析，以评估壳形变化及其相对频率的可能原因。基于μCT扫描，我们通过等周比率的二维和三维概括来估计材料效率，分别量化了旋涡横截面的面积与周长比率（二维）以及壳体积与表面积（三维）。我们发现，Stylommatophorans通过旋涡重叠优化了材料使用，这或许促进了扁平壳物种的多样化。Cyclophoroids由于其闭壳瓣而受到圆形横截面的限制；扁平壳相对较为罕见。两组在处理高壳形时均展现出相似的设计方案，由于前一轮和当前轮之间的双重重叠，局部几何形状的影响较小。我们的研究结果指出，材料效率是壳形选择中的驱动因素。从根本上讲，Stylommatophora的进化成功可能源于其制造经济型壳的更高灵活性。</p>