2019年12月5日，《科学》杂志在线发表了中国科学院古脊椎动物与古人类研究所毛方园、王元青与美国自然历史博物馆孟津等学者，关于早白垩基干兽类李氏源掠兽的研究成果。

基于多个3D骨骼标本，研究人员报告了一种新的白垩纪基干兽类哺乳动物，其听力和咀嚼器官与功能之间存在脱钩。听骨（包括上颌骨）与骨化的Meckel软骨没有骨骼接触；后者松散地放置在牙齿的后方。这种配置可能代表了确定的哺乳动物中耳的初始形态学阶段。

证据表明，听力和咀嚼器官已经以模块化的方式发展。在非哺乳动物齿形犬齿中以整合复合体开始，这两个模块受相似的发育和遗传机制调控，最终在哺乳动物的进化过程中分开，从而可以进一步改善听力和咀嚼效率。

附：英文原文

Title: Integrated hearing and chewing modules decoupled in a Cretaceous stem therian mammal

Author: Fangyuan Mao, Yaoming Hu, Chuankui Li, Yuanqing Wang, Morgan Hill Chase, Andrew K. Smith, Jin Meng

Issue&Volume: 2019/12/05

Abstract: Based on multiple 3D skeletal specimens we report a new Cretaceous stem therian mammal that displays decoupling of hearing and chewing apparatuses and functions. The auditory bones, including the surangular, have no bone contact with the ossified Meckel’s cartilage; the latter is loosely lodged on the medial rear of the dentary. This configuration probably represents the initial morphological stage of the definitive mammalian middle ear. Evidence shows that hearing and chewing apparatuses have evolved in a modular fashion. Starting as an integrated complex in non-mammaliaform cynodonts, the two modules, regulated by similar developmental and genetic mechanisms, eventually decoupled during the evolution of mammals, allowing further improvement for more efficient hearing and mastication.

DOI: 10.1126/science.aay9220

Source: https://science.sciencemag.org/content/early/2019/12/04/science.aay9220