How to Stick the Landing: Kangaroo Rats Use Their Tails to Reorient during Evasive Jumps Away from Predators
How to Stick the Landing: Kangaroo Rats Use Their Tails to Reorient during Evasive Jumps Away from Predators
复制标题
DOI：
10.1093/icb/icab043
复制
发表时间：
2021-05-03
影响因子：
2.6
通讯作者：
McGowan, Craig P.
中科院分区：
文献类型：
--
作者：
Schwaner, M. Janneke;Freymiller, Grace A.;McGowan, Craig P.
尾巴广泛存在于动物世界中，在运动任务中起着重要作用，如推进，操纵，稳定和操纵物体。袋鼠鼠是一种双足跳跃的啮齿类动物，在跳跃过程中用尾巴保持平衡，但在被捕食者攻击时，尾巴在垂直逃避跳跃中的作用还有待确定。因为我们观察到袋鼠大鼠在空中逃生跳跃时会在身体周围摆动尾巴，所以我们假设袋鼠大鼠在空中飞行时不仅用尾巴来稳定身体，而且还进行空中重新定向。我们收集的视频数据从自由放养的沙漠袋鼠大鼠（Dipodomys deserti）执行逃生跳跃响应模拟捕食者的攻击，并分析了他们的身体和尾巴在偏航平面（关于垂直轴）的旋转。袋鼠鼠的逃避反应是高度可变的。偏航时身体重新定向的幅度与跳跃高度、跳跃距离和腾空时间无关。袋鼠大鼠表现出逐步重新定位，而在空中，其中较慢的转折期对应的尾巴中心的质量被对齐接近垂直旋转轴的身体。为了检验跳跃过程中尾部运动对身体重新定向的影响，我们比较了角动量的平均变化率。尾部角动量的变化率几乎与身体的角动量成正比，这表明袋鼠大鼠在空中逃跑跳跃时，尾部使身体在偏航平面上重新定向。虽然袋鼠大鼠在逃跑跳跃过程中进行动态3D运动，但我们的数据表明袋鼠大鼠使用它们的尾巴来控制偏航平面中的方向。此外，我们表明，袋鼠大鼠很少使用他们的尾巴长度在偏航的全部潜力，这表明通过多个平面同时尾部运动的重要性。
Synopsis Tails are widespread in the animal world and play important roles in locomotor tasks, such as propulsion, maneuvering, stability, and manipulation of objects. Kangaroo rats, bipedal hopping rodents, use their tail for balancing during hopping, but the role of their tail during the vertical evasive escape jumps they perform when attacked by predators is yet to be determined. Because we observed kangaroo rats swinging their tails around their bodies while airborne following escape jumps, we hypothesized that kangaroo rats use their tails to not only stabilize their bodies while airborne, but also to perform aerial re-orientations. We collected video data from free-ranging desert kangaroo rats (Dipodomys deserti) performing escape jumps in response to a simulated predator attack and analyzed the rotation of their bodies and tails in the yaw plane (about the vertical-axis). Kangaroo rat escape responses were highly variable. The magnitude of body re-orientation in yaw was independent of jump height, jump distance, and aerial time. Kangaroo rats exhibited a stepwise re-orientation while airborne, in which slower turning periods corresponded with the tail center of mass being aligned close to the vertical rotation axis of the body. To examine the effect of tail motion on body re-orientation during a jump, we compared average rate of change in angular momentum. Rate of change in tail angular momentum was nearly proportional to that of the body, indicating that the tail reorients the body in the yaw plane during aerial escape leaps by kangaroo rats. Although kangaroo rats make dynamic 3D movements during their escape leaps, our data suggest that kangaroo rats use their tails to control orientation in the yaw plane. Additionally, we show that kangaroo rats rarely use their tail length at full potential in yaw, suggesting the importance of tail movement through multiple planes simultaneously.