The origins of Ornithodira (the last common ancestor of dinosaurs, pterosaurs, and their descendants) are yet to be resolved, and have the potential to inform on the diversification of some of the most intriguing ecologies and body forms to evolve in reptiles. A recent discovery of an extremely small ornithodiran archosaur by Christian Kammerer and colleagues is indicative of a miniaturisation event early in the evolution of Ornithodira. This raises questions about the evolution of characters associated with small body forms in these groups, such as flight and body surface integument.

中文翻译：

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Ornithodira 的小型化事件。

Ornithodira（恐龙、翼龙及其后代的最后一个共同祖先）的起源尚未解决，并且有可能为爬行动物进化的一些最有趣的生态和身体形态的多样化提供信息。Christian Kammerer 及其同事最近发现了一种极小的鸟龙类主龙，这表明在鸟龙类进化的早期发生了小型化事件。这引发了关于与这些群体中的小体型相关的特征进化的问题，例如飞行和体表外被。