Convergence of undulatory swimming kinematics across a diversity of fishes

Fishes exhibit an astounding diversity of locomotor behaviors, from classic swimming with their body and fins to jumping, flying, walking, and burrowing.  Fishes that use their body and caudal fin (BCF) during undulatory swimming have been traditionally divided into modes based on the length of the propulsive body wave and the ratio of head:tail oscillation amplitude: anguilliform, sub-carangiform, carangiform and thunniform. This classification was first proposed based on key morphological traits, such as body stiffness and elongation, to group fishes based on their expected swimming mechanics. Here, we present a comparative study of 44 diverse species quantifying kinematics and morphology of BCF-swimming fishes. Our results reveal that most species we studied share similar oscillation amplitude during steady locomotion that can be modeled using a second-degree order polynomial. The length of the propulsive body wave was shorter for species classified as anguilliform and longer for tho...

鱼类展现出惊人的运动行为多样性，从利用身体和鳍的典型游动，到跳跃、滑翔、爬行与穴居等多种方式。在波动式游动中利用身体和尾鳍（BCF）的鱼类，传统上根据推进性体波的长度以及头部与尾部振荡幅度的比值，被划分为不同模式：鳗形（anguilliform）、亚鲹形（sub-carangiform）、鲹形（carangiform）和金枪鱼形（thunniform）。该分类最初基于关键形态特征（如身体刚度与伸长率）提出，旨在根据鱼类预期的游动力学特性对其进行分组。本文针对44种不同鱼类开展比较研究，对BCF游动鱼类的运动学（kinematics）与形态学（morphology）特征进行量化分析。研究结果表明，我们所研究的大多数鱼类在稳定运动过程中具有相似的振荡幅度，且该幅度可通过二阶多项式建模。被归类为鳗形的鱼类，其推进性体波长度较短；而对于tho...（原文此处内容不完整）