Dataset for: Phenotypic disparity of the elbow joint in domestic dogs and wild carnivores

In this article, I use geometric morphometrics in 2D from a sample of 366 elbow joints to quantify phenotypic disparity in domestic dog breeds, in wild canids, and across the order Carnivora. The elbow joint is a well-established morphological indicator of forearm motion and, by extension, of functional adaptations towards locomotor or predatory behavior in living carnivores. The study of the elbow joint in domestic dogs allows the exploration of potential convergences between (i) pursuit predators and fast-running dogs, and (ii) ambush predators and fighting breeds. The results indicate that elbow shape disparity among domestic dogs exceeds that in wolves; it is comparable to the disparity of wild Caninae, but is significantly lower than the one observed throughout Canidae and Carnivora. Moreover, fast-running and fighting breeds are not convergent in elbow joint shape with extreme pursuit and ambush wild carnivores, respectively. The role of artificial selection and developmental constraints in shaping limb phenotypic disparity through the extremely fast evolution of the domestic dog is discussed in the light of this new evidence.

本研究采用基于366个肘关节样本的二维几何形态测量学（geometric morphometrics）方法，量化家犬品种、野生犬科动物以及食肉目（Carnivora）整体的表型差异（phenotypic disparity）。肘关节是公认的反映前肢运动的形态学指标，进而可用于反映现存食肉动物运动或掠食行为相关的功能适应性。针对家犬肘关节的研究，可用于探究两类潜在的趋同演化特征：一是追逐型掠食者与快跑犬品种之间，二是伏击型掠食者与斗犬品种之间。研究结果显示，家犬的肘关节形态差异大于灰狼；其差异水平与野生犬亚科（Caninae）相当，但显著低于整个犬科（Canidae）以及食肉目所观测到的差异水平。此外，快跑犬与斗犬品种的肘关节形态，并未分别与极端追逐型、伏击型野生食肉动物形成趋同的形态特征。结合本研究获得的新证据，本文探讨了人工选择与发育约束（developmental constraints）在塑造家犬极快演化进程中的肢体表型差异方面所起到的作用。