School of Mechanical and Electrical Engineering, Guilin University of Electronic Technology, Guilin, China.
Centre de Recherches en Paléobiodiversité et Paléoenvironnements, Muséum National d'Histoire Naturelle, Bâtiment de Paléontologie, CP38, 8 rue Buffon, 75005, Paris, France.
Sci Rep. 2017 Aug 31;7(1):10174. doi: 10.1038/s41598-017-10553-1.
Developmental changes in salamander skulls, before and after metamorphosis, affect the feeding capabilities of these animals. How changes in cranial morphology and tissue properties affect the function of the skull are key to decipher the early evolutionary history of the crown-group of salamanders. Here, 3D cranial biomechanics of the adult Salamandrella keyserlingii were analyzed under different tissue properties and ossification sequences of the cranial skeleton. This helped unravel that: (a) Mechanical properties of tissues (as bone, cartilage or connective tissue) imply a consensus between the stiffness required to perform a function versus the fixation (and displacement) required with the surrounding skeletal elements. (b) Changes on the ossification pattern, producing fontanelles as a result of bone loss or failure to ossify, represent a trend toward simplification potentially helping to distribute stress through the skull, but may also imply a major destabilization of the skull. (c) Bone loss may be originated due to biomechanical optimization and potential reduction of developmental costs. (d) Hynobiids are excellent models for biomechanical reconstruction of extinct early urodeles.
蝾螈头骨在变态前后的发育变化影响这些动物的进食能力。颅形态和组织特性的变化如何影响头骨的功能，是揭示有尾目蝾螈冠群早期进化历史的关键。在这里，分析了成年 Salamandrella keyserlingii 的 3D 颅部生物力学特性，考虑了颅骨骨骼的不同组织特性和骨化顺序。结果表明：（a）组织（如骨骼、软骨或结缔组织）的机械特性意味着执行功能所需的刚度与与周围骨骼元素的固定（和位移）之间存在一致性。（b）骨化模式的变化导致囟门的形成，这是由于骨丢失或骨化失败，代表了简化的趋势，有助于通过颅骨分布应力，但也可能意味着颅骨的严重不稳定。（c）骨丢失可能是由于生物力学优化和潜在的发育成本降低引起的。（d）小鲵科是重建已灭绝的早期有尾类生物力学模型的理想选择。
