Feeding strategies in sauropodomorphs: The evolution of extreme neck length and very large body size

非常长的脖子和它的利用对于理解蜥脚类动物的非对称性进化至关重要。然而，长颈的好处仍然是有争议的讨论。很明显，长脖子可以增加站立蜥脚类恐龙的进食量。然而，主要的好处可能是可以获得其他食草动物无法利用的高空食物资源，尽管已经提出了机械和生理上的论点来反对高浏览蜥脚类动物的想法。在这项研究中，一些保存完好的蜥脚类动物颈部的活动性将重新分析的颈椎虚拟三维模型。这些模型将基于原始椎骨或椎骨模型的扫描。在模型中，变形将被消除，不完整的椎骨将被重建，椎骨将被安排到蜥脚类动物颈部骨骼的3D模型。将添加软组织。基于这些颈部模型，精细的分析蜥脚类动物颈部的流动性和摄食量将进行。这些模型将通过对最近长颈脊椎动物的比较研究来验证：长颈鹿，骆驼和鸵鸟。对于不同的假设分布的食物，假设的喂养策略的能量效益将被估计和相关的颈部长度和身体大小。研究结果将表明，使用非常长的脖子是否可能是蜥脚类动物进化的触发因素或主要驱动因素。

The very long neck and its utilization are crucial for understanding the evolution of gigantism in sauropods. Yet, the benefit of the long neck is still discussed controversially. Clearly, the long neck allowed increasing the feeding volume of a standing sauropod. The main benefit, however, might have been the accessibility of food resources in great heights that could not be exploited by other herbivores, though mechanical as well as physiological arguments have been put forward against the idea of high browsing sauropods. In this study, the mobility of some well preserved sauropod necks will be reanalyzed by virtual 3D-models of neck vertebrae. The models will be based on scans of original vertebrae or casts of vertebrae. In the models, deformations will be eliminated, incomplete vertebrae will be reconstructed, and the vertebrae will be arranged to 3D-models of sauropod neck skeletons. Soft tissues will be added. Based on these neck models, refined analyses of sauropod neck mobility and feeding volumes will be conducted. The models will be validated by comparative studies on recent vertebrates with long necks: giraffes, camels, and ostriches. For different hypothetical distributions of food, the energy benefit of hypothetical feeding strategies will be estimated and related to neck length and body size. The results will show whether using a very long neck could have been the trigger or the major driving factor for the evolution of gigantism in sauropods.