Snap-jaw morphology is specialized for high-speed power amplification in the Dracula ant, Mystrium camillae
Snap-jaw morphology is specialized for high-speed power amplification in the Dracula ant, Mystrium camillae
复制标题
DOI：
10.1098/rsos.181447
复制
发表时间：
2018-12-01
影响因子：
3.5
通讯作者：
Suarez, Andrew, V
中科院分区：
文献类型：
--
作者：
Larabee, Fredrick J.;Smith, Adrian A.;Suarez, Andrew, V
动物速度的极限是多少？什么机制产生最快的运动？这个答案不仅仅是自然历史的琐事，还提供了对肌肉骨骼运动的形式与功能关系的关键见解，并且可以确定捕食者与猎物相互作用的结果。已知运动最快的动物属于节肢动物，包括陷颌蚁、螳螂虾和蛙跳，它们将闩锁和弹簧纳入其附肢系统中，以克服肌肉力量的限制。与这些功率放大的例子相反，在这些例子中，单独的结构充当闩锁和弹簧来加速附肢，一些动物使用“卡爪”机构，将闩锁和弹簧结合在加速附肢本身上。我们研究了德古拉蚂蚁（Mystrium camillae）的运动学和功能形态，它们使用咬合装置快速地将下颌骨彼此滑动，类似于打响指。对高速视频的运动学分析显示，断口蚁下颌在短短 23 微秒内完成攻击，并达到 90 毫秒(-1) 的峰值速度，使其成为已知最快的动物附肢。有限元分析表明，咬合下颌骨的硬度低于咬合非功率放大的下颌骨，这与它们作为柔性弹簧的用途一致。这些结果扩展了我们对动物速度的理解，并证明了形态上的微小变化可以如何导致性能上的巨大差异。
What is the limit of animal speed and what mechanisms produce the fastest movements? More than natural history trivia, the answer provides key insight into the form-function relationship of musculoskeletal movement and can determine the outcome of predator-prey interactions. The fastest known animal movements belong to arthropods, including trap-jaw ants, mantis shrimp and froghoppers, that have incorporated latches and springs into their appendage systems to overcome the limits of muscle power. In contrast to these examples of power amplification, where separate structures act as latch and spring to accelerate an appendage, some animals use a 'snap-jaw' mechanism that incorporates the latch and spring on the accelerating appendage itself. We examined the kinematics and functional morphology of the Dracula ant, Mystrium camillae, who use a snap-jaw mechanism to quickly slide their mandibles across each other similar to a finger snap. Kinematic analysis of high-speed video revealed that snap-jaw ant mandibles complete their strike in as little as 23 mu sec and reach peak velocities of 90 ms(-1) making them the fastest known animal appendage. Finite-element analysis demonstrated that snap-jaw mandibles were less stiff than biting non-power-amplified mandibles, consistent with their use as a flexible spring. These results extend our understanding of animal speed and demonstrate how small changes in morphology can result in dramatic differences in performance.