西班牙巴塞罗那大学Olmo Miguez-Salas团队研究了埃迪卡拉纪运动痕迹化石形态的定量解码：细长前后体轮廓出现的证据。相关论文于2025年6月9日发表在《地质学》杂志上。

遗迹化石对于研究埃迪卡拉纪末期早期动物及其与古环境的共同进化至关重要，这是一个身体化石记录稀少的时期。因此，埃迪卡拉纪痕迹标记的形态演化模式很难理清，在数量上也没有得到探索。研究组使用积分尺度作为轨迹制造者运动特征长度的潜在指标，积分尺度反映了轨迹（即力和位移）自相关的距离。通过分析现代和化石动物痕迹相关轨迹，发现特征运动长度与轨迹积分尺度之间存在正比关系。

由于产生运动的结构的长度不大于身体的长度，因此特征运动长度也反映了最小身体长度。将这一比例定律应用于埃迪卡拉纪-寒武纪的运动痕迹化石（如Archaeonassa、Gordia、Helminthopsis、Parapsamichnites），研究组在大约545 Ma后发现了细长的前后体轴的明确证据，最小体长宽比逐渐增加到4−12。 

痕迹制造者可能拥有相对刚性的身体，具有强大的静水神经肌肉系统，可以增强方向感和运动，使其能够在动态复杂、异质和不断变化的栖息地中茁壮成长。这些适应可能推动了生态位划分和级联多样化，巩固了寒武纪爆发和显生宙更熟悉的动物的进化根源。该发现为研究深部运动痕迹化石建立了一种新的定量方法，为早期动物解剖学和古生态动力学提供了强有力的见解。

附：英文原文

Title: Quantitative decoding of Ediacaran locomotory trace fossil morphologies: Evidence for the emergence of slender anterior-posterior body profiles

Author: Zekun Wang, Olmo Miguez-Salas

Issue&Volume: 2025-06-09

Abstract: Trace fossils are vital for studying early animals and their co-evolution with paleoenvironments during the terminal Ediacaran, a period with sparse body fossil records. Thus, patterns of morphologic evolution are difficult to untangle for Ediacaran trace-makers and quantitatively unexplored. In this study, we use the integral scale, which reflects the distance within which a trajectory (i.e., force and displacement) is self-correlated, as a potential indicator for the characteristic length of trace-maker’s locomotion. By analyzing modern and fossilized animal-trace-correlated trajectories, a proportionality between the characteristic locomotory length and the trajectory integral scale is found. Since the length of the structure producing locomotion is no larger than that of the body, the characteristic locomotory length also reflects the minimal body length. Applying this scaling law to EdiacaranCambrian locomotory trace fossils (e.g., Archaeonassa, Gordia, Helminthopsis, Parapsammichnites), we identify clear evidence of slender anterior-posterior body axes after around 545 Ma, with gradually increasing minimal body length-to-width ratios to up to 412. The trace-makers probably had relatively rigid bodies with robust hydrostatic nerve-muscle systems enhancing directional sensation and movement, enabling them to thrive in dynamically complex, heterogeneous, and shifting habitats. These adaptations likely drove niche partitioning and cascading diversification, underpinning the evolutionary roots of the Cambrian Explosion and more familiar animals of the Phanerozoic. Our findings establish a novel quantitative approach to studying deep-time locomotory trace fossils, offering robust insights into early animal anatomy and paleoecological dynamics.

DOI: 10.1130/G53332.1

Source: https://pubs.geoscienceworld.org/gsa/geology/article/doi/10.1130/G53332.1/655874/Quantitative-decoding-of-Ediacaran-locomotory