English A W
J Morphol. 1977 Mar;151(3):325-52. doi: 10.1002/jmor.1051510303.
Dissections, manipulation of ligamentary preparations, analysis of limb proportions, and quantitative aspects of forelimb myology are used to correlate forelimb morphology in fur seals and sea lions (sub-family Otariinae) with previously published data as to their locomotor function (English, '76a). Comparisons to structure and function in generalized fissiped carnivores are then used to elucidate locomotor adaptations in fur seals and sea lions. Unique features of forelimb function during swimming in these pinnipeds include the amounts of abduction-adduction and rotary movements used. Modifications of the size, attachments and fasicle architecture of the muscles and the structure and range of possible movement of the joints suggest that in fur seals and sea lions these movements (1) take place about the glenohumeral (shoulder) joints, (2) that the movements are probably finely controlled, and (3) that they contribute to the generation of massive forward thrust via the cooperative activity of muscles capable of generating large amounts of force throughout the range of movement. Recovery movements occur through a similarly large range, and modifications of forelimb anatomy either to minimize or overcome water resistance are noted. The adaptive significance of these modifications is interpreted as allowing fur seals and sea lions to swim at speeds necessary to feed on the fast swimming prey presumably abundant in their adaptive zone.
解剖、韧带标本的操作、肢体比例分析以及前肢肌肉学的定量研究，被用于将海狗和海狮（海狗亚科）的前肢形态与先前发表的关于其运动功能的数据相关联（English，1976a）。随后，通过与广义裂脚食肉动物的结构和功能进行比较，来阐明海狗和海狮的运动适应性。这些鳍足类动物在游泳时前肢功能的独特特征包括外展 - 内收和旋转运动的幅度。肌肉大小、附着点和肌束结构的改变以及关节的结构和可能运动范围表明，在海狗和海狮中，这些运动：（1）发生在肩胛肱（肩）关节周围；（2）这些运动可能受到精细控制；（3）它们通过在整个运动范围内能够产生大量力量的肌肉的协同活动，有助于产生巨大的向前推力。恢复运动也通过类似的大范围进行，并且注意到前肢解剖结构的改变，以最小化或克服水阻力。这些改变的适应性意义被解释为使海狗和海狮能够以其适应区域中可能丰富的快速游动猎物为食所需的速度游泳。
