López-Romero Faviel A, Villalobos-Segura Eduardo, Türtscher Julia, Berio Fidji, Stumpf Sebastian, Dearden Richard P, Kriwet Jürgen, Maldonado Ernesto
EvoDevo Research Group, Unidad de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, C.P. 77580 Quintana Roo México.
Evolutionary Morphology Research Group, Department of Palaeontology, Faculty of Earth Sciences, Geography and Astronomy, University of Vienna, Josef-Holaubek-Platz 2, 1190 Vienna, Austria.
Evol Ecol. 2025;39(1):111-134. doi: 10.1007/s10682-025-10330-x. Epub 2025 Feb 17.
Batoids (skates and rays) are the most speciose group of cartilaginous fishes with a diverse array of ecological adaptations and swimming modes. Early skeletal fossil remains and recent phylogenetic analyses suggest that convergence among batoids has occurred independently multiple times. The drivers for such disparity patterns and possible association with modularity and phenotypic integration among batoids are not fully understood. Here we employed geometric morphometrics and phylogenetic comparative methods to characterize the evolutionary trends in the basal fin skeleton of extinct and extant batoids and dorsoventrally flattened sharks. We found that the most speciose orders of batoids, Myliobatiformes and Rajiformes, display the lowest levels of morphological disparity, while Torpediniformes and Rhinopristitiformes have the highest disparity. Differences in evolutionary rates by habitat indicate that both reef and freshwater species evolved faster than deep-sea and shelf-distributed species. We further explored the differences based on swimming modes and found that species with oscillatory swimming exhibit higher evolutionary rates on their coracoid bar. We found that specific groups underwent different rates of evolution on each element of the pectoral fin. This was corroborated by the modularity and integration analyses, which indicate differences in the covariation between structures among the analyzed groups. The convergence analysis does not support the resemblance between flattened sharks and batoids; however we found convergence between extinct batoids and modern guitarfishes. Our findings suggest that habitat and swimming mode have shaped the pectoral fin evolution among batoids.
The online version contains supplementary material available at 10.1007/s10682-025-10330-x.
鳐类（鳐和魟）是软骨鱼类中种类最多的群体，具有各种各样的生态适应性和游泳方式。早期的骨骼化石遗迹和最近的系统发育分析表明，鳐类之间的趋同现象已经多次独立发生。这种差异模式的驱动因素以及与鳐类模块化和表型整合的可能关联尚未完全了解。在这里，我们采用几何形态计量学和系统发育比较方法来描述已灭绝和现存鳐类以及背腹扁平鲨鱼的基底鳍骨骼的进化趋势。我们发现，鳐类中种类最多的目，鲼形目和鳐形目，形态差异水平最低，而电鳐目和尖犁头鳐目差异最大。按栖息地划分的进化速率差异表明，礁栖和淡水物种的进化速度都比深海和分布在陆架的物种快。我们进一步根据游泳方式探索了差异，发现采用摆动式游泳的物种在喙骨上的进化速率更高。我们发现特定群体在胸鳍的每个元素上经历了不同的进化速率。模块化和整合分析证实了这一点，这些分析表明所分析群体中结构之间的协变存在差异。趋同分析不支持扁平鲨鱼和鳐类之间的相似性；然而，我们发现已灭绝的鳐类和现代犁头鳐之间存在趋同现象。我们的研究结果表明，栖息地和游泳方式塑造了鳐类胸鳍的进化。
在线版本包含可在10.1007/s10682 - 025 - 10330 - x获取的补充材料。
