Departement of Earth and Planetary Sciences, University of California, Davis, Davis, California, United States of America.
PeerJ. 2023 Aug 24;11:e15957. doi: 10.7717/peerj.15957. eCollection 2023.
Body mass is arguably the most important characteristic of an organism, yet it is often not available in biological samples that have been skeletonized, liquid-preserved, or fossilized. The lack of information is especially problematic for fossil species, for which individuals with body mass information are not available anywhere. Multiple methods are available for estimating the body mass of fossil terrestrial vertebrates but those for their marine counterparts are limited. Paleomass is a software tool for estimating the body mass of marine vertebrates from their orthogonal silhouettes through bracketing. It generates a set of two 3D models from these silhouettes, assuming superelliptical body cross-sections with different exponent values. By setting the exponents appropriately, it is possible to bracket the true volume of the animal between those of the two models. The original version phased out together with the language platform it used. A new version is reported here as an open-source package based on the R scripting language. It inherits the underlying principles of the original version but has been completely rewritten with a new architecture. For example, it first produces 3D mesh models of the animal and then measures their volumes and areas with the VCG library, unlike the original version that did not produce a 3D model but instead computed the volume and area segment by segment using parametric equations. The new version also exports 3D models in polygon meshes, allowing later tests by other software. Other improvements include the use of NACA foil sections for hydrofoils such as flippers, and optional interpolation with local regression. The software has a high accuracy, with the mean absolute errors of 1.33% when the silhouettes of the animals are known.
体质量可以说是生物体最重要的特征，但在骨骼化、液体保存或化石化的生物样本中，它往往无法获得。对于化石物种来说，信息的缺乏尤其成问题，因为这些物种的个体在任何地方都无法获得体质量信息。有多种方法可用于估算化石陆生脊椎动物的体质量，但对于海洋脊椎动物的方法却有限。Paleomass 是一种通过框定估算海洋脊椎动物体质量的软件工具，它通过框定从其正交轮廓估算海洋脊椎动物的体质量。它从这些轮廓生成两个 3D 模型，假设具有不同指数值的超椭圆截面。通过适当设置指数，可以在两个模型之间框定动物的真实体积。最初的版本与它所使用的语言平台一起淘汰。本文报告了一个新版本，它是一个基于 R 脚本语言的开源软件包。它继承了原始版本的基本原则，但具有全新的架构。例如，它首先生成动物的 3D 网格模型，然后使用 VCG 库测量它们的体积和面积，而不是原始版本，原始版本不生成 3D 模型，而是使用参数方程逐段计算体积和面积。新版本还以多边形网格的形式导出 3D 模型，允许其他软件进行后续测试。其他改进包括在水翼（如鳍状肢）等使用 NACA 翼型剖面，以及可选的局部回归插值。该软件具有很高的准确性，当动物的轮廓已知时，其平均绝对误差为 1.33%。
