Shaffer Irena, Abaid Nicole
Engineering Mechanics Program, Virginia Tech, Blacksburg, VA 24061, USA.
Department of Mathematics, Virginia Tech, Blacksburg, VA 24061, USA.
Entropy (Basel). 2020 Oct 19;22(10):1176. doi: 10.3390/e22101176.
Many animal species, including many species of bats, exhibit collective behavior where groups of individuals coordinate their motion. Bats are unique among these animals in that they use the active sensing mechanism of echolocation as their primary means of navigation. Due to their use of echolocation in large groups, bats run the risk of signal interference from sonar jamming. However, several species of bats have developed strategies to prevent interference, which may lead to different behavior when flying with conspecifics than when flying alone. This study seeks to explore the role of this acoustic sensing on the behavior of bat pairs flying together. Field data from a maternity colony of gray bats were collected using an array of cameras and microphones. These data were analyzed using the information theoretic measure of transfer entropy in order to quantify the interaction between pairs of bats and to determine the effect echolocation calls have on this interaction. This study expands on previous work that only computed information theoretic measures on the 3D position of bats without echolocation calls or that looked at the echolocation calls without using information theoretic analyses. Results show that there is evidence of information transfer between bats flying in pairs when time series for the speed of the bats and their turning behavior are used in the analysis. Unidirectional information transfer was found in some subsets of the data which could be evidence of a leader-follower interaction.
许多动物物种，包括许多蝙蝠物种，都表现出集体行为，即个体群体协调它们的运动。蝙蝠在这些动物中是独特的，因为它们将回声定位的主动传感机制作为其主要导航手段。由于它们在大群体中使用回声定位，蝙蝠面临着声纳干扰导致信号干扰的风险。然而，几种蝙蝠已经开发出防止干扰的策略，这可能导致与同种蝙蝠一起飞行时的行为与单独飞行时不同。本研究旨在探讨这种声学传感对一起飞行的蝙蝠对行为的作用。使用一系列相机和麦克风收集了灰蝙蝠繁殖群体的现场数据。使用转移熵的信息论度量对这些数据进行分析，以量化蝙蝠对之间的相互作用，并确定回声定位叫声对这种相互作用的影响。本研究扩展了以前的工作，以前的工作仅对没有回声定位叫声的蝙蝠的三维位置计算信息论度量，或者在不使用信息论分析的情况下研究回声定位叫声。结果表明，当在分析中使用蝙蝠速度及其转弯行为的时间序列时，有证据表明成对飞行的蝙蝠之间存在信息传递。在数据的一些子集中发现了单向信息传递，这可能是领导者-跟随者相互作用的证据。
