Depecker Marion, Berge Christine, Penin Xavier, Renous Sabine
Muséum National d'Histoire Naturelle, Paris, France.
J Anat. 2006 Jan;208(1):35-45. doi: 10.1111/j.1469-7580.2006.00512.x.
The aim of this study was to identify shape patterns of the shoulder girdle in relation to different functional and environmental behaviours in turtles. The Procrustes method was used to compare the shoulder girdles (scapula and coracoid) of 88 adult extant turtles. The results indicate that four shape patterns can be distinguished. The shoulder girdles of (1) terrestrial (Testudinidae), (2) highly aquatic freshwater (Trionychidae, Carettochelyidae) and (3) marine turtles (Cheloniidae, Dermochelyidae) correspond to three specialized morphological patterns, whereas the shoulder girdle of (4) semi-aquatic freshwater turtles (Bataguridae, Chelidae, Chelydridae, Emydidae, Kinosternidae, Pelomedusidae, Platysternidae, Podocnemididae) is more generalized. In terrestrial turtles, the long scapular prong and the short coracoid are associated with a domed shell and a mode of locomotion in which walking is predominant. By contrast, highly aquatic freshwater turtles share traits with marine turtles. In both, the short scapular prong and the long coracoid are associated with a flat shell, and swimming locomotion. The enlarged attachment sites of the biceps, coracobrachialis magnus, and supracoracoideus also give these strong swimmers a mechanical advantage during adduction and retraction of the arm. Increasing size leads to allometrical shape changes that emphasize mechanical efficiency both in terrestrial and in aquatic turtles.
本研究的目的是确定龟类肩带的形状模式与不同功能和环境行为之间的关系。采用普洛卡斯特斯方法比较了88只成年现存龟类的肩带（肩胛骨和喙骨）。结果表明，可以区分出四种形状模式。（1）陆龟（陆龟科）、（2）高度水生的淡水龟（鳖科、两爪鳖科）和（3）海龟（海龟科、棱皮龟科）的肩带对应三种特化的形态模式，而（4）半水生淡水龟（地龟科、蛇颈龟科、鳄龟科、水龟科、动胸龟科、侧颈龟科、平胸龟科、泥龟科）的肩带则更为一般化。在陆龟中，长的肩胛骨叉和短的喙骨与圆顶壳以及以行走为主的运动方式相关。相比之下，高度水生的淡水龟与海龟有共同特征。在这两类龟中，短的肩胛骨叉和长的喙骨与扁平壳以及游泳运动相关。肱二头肌、肱大喙肱肌和喙上肌附着点的扩大也使这些强壮的游泳者在手臂内收和后缩时具有机械优势。体型增大导致异速生长的形状变化，这在陆龟和水龟中都强调了机械效率。
