Hatala Kevin G, Gatesy Stephen M, Falkingham Peter L
Department of Biology, Chatham University, Pittsburgh, PA 15232, USA.
Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, USA.
Interface Focus. 2021 Aug 13;11(5):20200075. doi: 10.1098/rsfs.2020.0075. eCollection 2021 Oct 6.
The emergence of bipedalism had profound effects on human evolutionary history, but the evolution of locomotor patterns within the hominin clade remains poorly understood. Fossil tracks record behaviours of extinct hominins, and they offer great potential to reveal locomotor patterns at various times and places across the human fossil record. However, there is no consensus on how to interpret anatomical or biomechanical patterns from tracks due to limited knowledge of the complex foot-substrate interactions through which they are produced. Here, we implement engineering-based methods to understand human track formation with the ultimate goal of unlocking invaluable information on hominin locomotion from fossil tracks. We first developed biplanar X-ray and three-dimensional animation techniques that permit visualization of subsurface foot motion as tracks are produced, and that allow for direct comparisons of foot kinematics to final track morphology. We then applied the discrete element method to accurately simulate the process of human track formation, allowing for direct study of human track ontogeny. This window lets us observe how specific anatomical and/or kinematic variables shape human track morphology, and it offers a new avenue for robust hypothesis testing in order to infer patterns of foot anatomy and motion from fossil hominin tracks.
两足行走的出现对人类进化史产生了深远影响，但人族谱系内运动模式的进化仍知之甚少。化石足迹记录了已灭绝人族的行为，它们为揭示人类化石记录中不同时间和地点的运动模式提供了巨大潜力。然而，由于对足迹产生过程中复杂的足部与基质相互作用了解有限，对于如何从足迹中解读解剖学或生物力学模式尚无共识。在此，我们采用基于工程学的方法来理解人类足迹的形成，最终目标是从化石足迹中解锁有关人族运动的宝贵信息。我们首先开发了双平面X射线和三维动画技术，这些技术能够在足迹形成过程中可视化足部的地下运动，并能将足部运动学与最终足迹形态进行直接比较。然后，我们应用离散元方法精确模拟人类足迹形成过程，从而直接研究人类足迹的个体发生。这个窗口使我们能够观察特定的解剖学和/或运动学变量如何塑造人类足迹形态，并且为进行有力的假设检验提供了一条新途径，以便从化石人族足迹中推断足部解剖结构和运动模式。
