The ant Odontomachus monticola has a pair of elongated mandibles that can manipulate a variety of objects including food, brood and nestmates. Anatomical and theoretical studies indicate that different tasks may require modification of mandible speed and force which is achieved by modulating the respective activity of three sets of muscles. Despite the advanced investigations on how muscles separately control the mandible movements in trap-jaw ants, real-time visualization of the muscle activity has remained elusive. In this investigation, we developed an approach based on the synchrotron imaging technique to elucidate the real-time topology of the muscles in the head of the ant. Using synchrotron imaging, we described the topology of the living ant’s mandible muscles and calculated area changes in the intracranial muscles, which reflected the respective muscle’s activities in the strike of mandibles. This study provides the first visualization evidence which validates that the mandible strike is facilitated by the contraction of adductor muscles, without the activation of abductor muscles.

中文翻译：

---

通过同步加速器成像观察和量化陷阱颚蚂蚁 Odontomachus monticola 中实时下颌肌肉拓扑结构的方法

蚂蚁 Odontomachus monticola 有一对细长的下颌骨，可以操纵各种物体，包括食物、巢穴和巢穴。解剖学和理论研究表明，不同的任务可能需要改变下颌骨的速度和力量，这是通过调节三组肌肉的相应活动来实现的。尽管对肌肉如何分别控制陷阱颚蚂蚁的下颌运动进行了深入研究，但肌肉活动的实时可视化仍然难以实现。在这项调查中，我们开发了一种基于同步加速器成像技术的方法来阐明蚂蚁头部肌肉的实时拓扑结构。使用同步加速器成像，我们描述了活蚂蚁下颌肌肉的拓扑结构并计算出颅内肌肉的面积变化，这反映了下颌骨撞击时各自肌肉的活动。这项研究提供了第一个可视化证据，它验证了内收肌的收缩促进了下颌骨撞击，而没有激活外展肌。