Data from: Three-dimensional reconstructions come to life – interactive 3D PDF animations in functional morphology

Digital surface mesh models based on segmented datasets have become an integral part of studies on animal anatomy and functional morphology; usually, they are published as static images, movies or as interactive PDF files. We demonstrate the use of animated 3D models embedded in PDF documents, which combine the advantages of both movie and interactivity, based on the example of preserved Trigonopterus weevils. The method is particularly suitable to simulate joints with largely deterministic movements due to precise form closure. We illustrate the function of an individual screw-and-nut type hip joint and proceed to the complex movements of the entire insect attaining a defence position. This posture is achieved by a specific cascade of movements: Head and legs interlock mutually and with specific features of thorax and the first abdominal ventrite, presumably to increase the mechanical stability of the beetle and to maintain the defence position with minimal muscle activity. The deterministic interaction of accurately fitting body parts follows a defined sequence, which resembles a piece of engineering.

基于分割数据集构建的数字化表面网格模型（Digital surface mesh models）现已成为动物解剖学与功能形态学研究的核心组成部分；这类模型通常以静态图像、影片或交互式PDF文档的形式公开发布。本研究以馆藏锥象甲属（Trigonopterus）象鼻虫标本为案例，演示了嵌入PDF文档的动态3D模型的应用方案——该模型兼具影片展示与交互操作的双重优势。该方法尤其适用于模拟通过精准形态闭合实现、具备高度确定性运动特征的关节。我们先阐释了单个螺杆螺母型髋关节的运作原理，随后展示了整只昆虫进入防御姿态时的复杂运动过程。该防御姿态通过一系列特定的连续运动序列达成：头部与腿部相互扣合，同时与胸部及第一腹腹板的特化结构嵌合，推测此举可提升甲虫的机械稳定性，并以最低限度的肌肉活动维持防御姿态。各精准适配的身体部位间的确定性交互遵循既定序列，其运作机制宛如一件精密工程制品。