科学家已经根据化石牙齿上的划痕和磨损的模式重建了鸭嘴恐龙——埃德蒙顿龙（Edmontosaurus）的饮食习惯。
Mark Purnell根据这些痕迹确定了埃德蒙顿龙以矮生植被为食，而不是以木质细枝和树叶为食。像植食性的埃德蒙顿龙这样的恐龙在白垩纪晚期是最大型的脊椎动物之一，而它们觅食的成功归功于它们的头骨结构，与绝大多数恐龙不同，这种结构让它们能咀嚼并磨碎它们的食物。尽管脊椎动物牙齿化石可以提供一些饮食的线索，仍然不清楚埃德蒙顿龙究竟吃哪种食物，以及它们如何咀嚼它。
这组科学家发现，埃德蒙顿龙牙齿上的划痕表明主要存在上下的颌骨运动，以及一些前后运动。这支持了一种观点，即这种恐龙的头骨上有一个挠性关节，而这些划痕模式表明了紧密约束的咀嚼运动。这组科学家说，尽管这些化石牙齿被划痕覆盖，它们没有凹坑和缺口，这标志着一种磨损的模式，在现存的植食动物中该模式是吃草的动物的特征。（生物谷Bioon.com）
生物谷推荐原始出处：
PNAS June 29, 2009, doi: 10.1073/pnas.0812631106
Quantitative analysis of dental microwear in hadrosaurid dinosaurs, and the implications for hypotheses of jaw mechanics and feeding
Vincent S. Williamsa, Paul M. Barrettb and Mark A. Purnell
Understanding the feeding mechanisms and diet of nonavian dinosaurs is fundamental to understanding the paleobiology of these taxa and their role in Mesozoic terrestrial ecosystems. Various methods, including biomechanical analysis and 3D computer modeling, have been used to generate detailed functional hypotheses, but in the absence of either direct observations of dinosaur feeding behavior, or close living functional analogues, testing these hypotheses is problematic. Microscopic scratches that form on teeth in vivo during feeding are known to record the relative motion of the tooth rows to each other during feeding and to capture evidence of tooth–food interactions. Analysis of this dental microwear provides a powerful tool for testing hypotheses of jaw mechanics, diet, and trophic niche; yet, quantitative analysis of microwear in dinosaurs has not been attempted. Here, we show that analysis of tooth microwear orientation provides direct evidence for the relative motions of jaws during feeding in hadrosaurid ornithopods, the dominant terrestrial herbivores of the Late Cretaceous. Statistical testing demonstrates that Edmontosaurus teeth preserve 4 distinct sets of scratches in different orientations. In terms of jaw mechanics, these data indicate an isognathic, near-vertical posterodorsal power stroke during feeding; near-vertical jaw opening; and propalinal movements in near anterior and near posterior directions. Our analysis supports the presence of a pleurokinetic hinge, and the straightness and parallelism of scratches indicate a tightly controlled occlusion. The dominance of scratched microwear fabrics suggests that Edmontosaurus was a grazer rather than a browser.
