Data from: Modularity and rates of evolutionary change in a power-amplified prey capture system

The dynamic interplay among structure, function and phylogeny form a classic triad of influences on the patterns and processes of biological diversification. While these dynamics are widely recognized as important, quantitative analyses of their interactions have infrequently been applied to biomechanical systems. Here we analyze these factors using a fundamental biomechanical mechanism: power amplification. Power-amplified systems use springs and latches to generate extremely fast and powerful movements. This study focuses specifically on the power amplification mechanism in the fast raptorial appendages of mantis shrimp (Crustacea: Stomatopoda). Using geometric morphometric and phylogenetic comparative analyses, we measured evolutionary modularity and rates of morphological evolution of the raptorial appendage’s biomechanical components. We found that “smashers” (hammer-shaped raptorial appendages) exhibit lower modularity and 10-fold slower rates of morphological change when compared to non-smashers (spear-shaped or undifferentiated appendages). The morphological and biomechanical integration of this system at a macro-evolutionary scale and the presence of variable rates of evolution reveal a balance between structural constraints, functional variation, and the developmental and genetic roles in evolutionary diversification.

结构、功能与系统发育之间的动态相互作用，构成了影响生物多样化模式与过程的经典三重影响因素。尽管这些动态关联已被广泛认可其重要性，但针对三者间相互作用的定量分析，却极少被应用于生物力学系统研究中。本研究借助一种基础生物力学机制——功率放大（power amplification），对上述三类因素展开分析。功率放大系统通过弹簧与锁扣结构，实现极快且强力的运动输出。本研究聚焦于螳螂虾（甲壳纲：口足目）快速掠食附肢中的功率放大机制。研究采用几何形态测量法（geometric morphometric）与系统发育比较分析，对掠食附肢生物力学组分的进化模块化程度与形态进化速率进行量化分析。结果显示，与非粉碎型（矛状或未分化附肢）类群相比，粉碎型（锤状掠食附肢）类群的模块化程度更低，且形态变化速率仅为前者的十分之一。该系统在宏观进化尺度下的形态与生物力学整合性，以及进化速率的异质性，揭示了结构约束、功能变异，与发育及遗传因素在生物多样化进程中所形成的动态平衡。