美国耶鲁大学Bhart-Anjan S. Bhullar小组的研究揭示了鸟状内耳的早期起源以及其与运动和发声演变的关系。相关论文发表在2021年5月7日出版的《科学》杂志上。

研究人员对大量现存和已灭绝的爬行动物进行了三维形态计量学分析，以研究运动能力和听力敏锐度与内耳的关系。统计分析显示了三种前庭形态，这可用三种运动类别来解释：四足动物、两足动物和简单飞行动物（包括两足动物非动物学恐龙）和高等飞行动物。Troodontids与始祖鸟一起归入现存的低等飞行动物类别。对耳蜗形状的分析表明，始祖龙的茎存在伸长现象。研究人员认为这种转变与幼鸟对高音调位置、警报、孵化信号和以及成年个体对其反应的发生相吻合。

据了解，包括鸟类在内的爬行动物表现出一系列与行为相关的适应性变化，这些适应性变化反映在内耳结构的变化中。这些改变包括飞行能力和对高频声音的敏感性。

附：英文原文

Title: The early origin of a birdlike inner ear and the evolution of dinosaurian movement and vocalization

Author: Michael Hanson, Eva A. Hoffman, Mark A. Norell, Bhart-Anjan S. Bhullar

Issue&Volume: 2021/05/07

Abstract: Reptiles, including birds, exhibit a range of behaviorally relevant adaptations that are reflected in changes to the structure of the inner ear. These adaptations include the capacity for flight and sensitivity to high-frequency sound. We used three-dimensional morphometric analyses of a large sample of extant and extinct reptiles to investigate inner ear correlates of locomotor ability and hearing acuity. Statistical analyses revealed three vestibular morphotypes, best explained by three locomotor categories—quadrupeds, bipeds and simple fliers (including bipedal nonavialan dinosaurs), and high-maneuverability fliers. Troodontids fall with Archaeopteryx among the extant low-maneuverability fliers. Analyses of cochlear shape revealed a single instance of elongation, on the stem of Archosauria. We suggest that this transformation coincided with the origin of both high-pitched juvenile location, alarm, and hatching-synchronization calls and adult responses to them.

DOI: 10.1126/science.abb4305

Source: https://science.sciencemag.org/content/372/6542/601