Roy Subhradeep, Howes Kayla, Müller Rolf, Butail Sachit, Abaid Nicole
Physical Computing Lab., Virginia Tech, Blacksburg, VA 24061, USA.
Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA.
Entropy (Basel). 2019 Jan 9;21(1):42. doi: 10.3390/e21010042.
Social animals exhibit collective behavior whereby they negotiate to reach an agreement, such as the coordination of group motion. Bats are unique among most social animals, since they use active sensory echolocation by emitting ultrasonic waves and sensing echoes to navigate. Bats' use of active sensing may result in acoustic interference from peers, driving different behavior when they fly together rather than alone. The present study explores quantitative methods that can be used to understand whether bats flying in pairs move independently of each other or interact. The study used field data from bats in flight and is based on the assumption that interactions between two bats are evidenced in their flight patterns. To quantify pairwise interaction, we defined the strength of coupling using model-free methods from dynamical systems and information theory. We used a control condition to eliminate similarities in flight path due to environmental geometry. Our research question is whether these data-driven methods identify directed coupling between bats from their flight paths and, if so, whether the results are consistent between methods. Results demonstrate evidence of information exchange between flying bat pairs, and, in particular, we find significant evidence of rear-to-front coupling in bats' turning behavior when they fly in the absence of obstacles.
群居动物表现出集体行为，通过协商达成一致，比如群体运动的协调。蝙蝠在大多数群居动物中很独特，因为它们通过发出超声波并感知回声来进行主动感官回声定位以导航。蝙蝠使用主动感知可能会导致来自同伴的声学干扰，使得它们一起飞行时的行为与单独飞行时不同。本研究探索了可用于理解成对飞行的蝙蝠是彼此独立移动还是相互作用的定量方法。该研究使用了蝙蝠飞行的实地数据，并基于这样的假设：两只蝙蝠之间的相互作用在它们的飞行模式中有所体现。为了量化成对相互作用，我们使用来自动力系统和信息论的无模型方法定义了耦合强度。我们使用了一个控制条件来消除由于环境几何形状导致的飞行路径相似性。我们的研究问题是这些数据驱动的方法能否从蝙蝠的飞行路径中识别出它们之间的定向耦合，如果能，这些方法的结果是否一致。结果证明了飞行中的蝙蝠对之间存在信息交换的证据，特别是，我们发现当蝙蝠在没有障碍物的情况下飞行时，它们转弯行为中存在从后向前耦合的显著证据。
