Spatio-temporal dynamics of an acoustic communication network: how echolocating bats communicate and orient in free-flying groups

交流和运动是动物之间进行社会互动的关键行为。在蝙蝠的回声定位中，交流和运动是自然结合的：在飞行过程中，蝙蝠通过倾听自己强大叫声的回声来“与自己交流”。这种持续不断的叫声也能被其他蝙蝠听到，并告知它们发送者的位置和行为。除了回声定位呼叫外，蝙蝠在飞行过程中还会发出各种各样的社会呼叫，用于个体间的交流。这两种声音行为使蝙蝠成为最会说话的哺乳动物；它们在飞行过程中的声通信网络是密集的，时空动态的，并且涉及不同物种的不同声刺激。因此，蝙蝠的回声定位是揭示经过进化测试的通信和导航策略的理想选择，这将促进我们对行为原理的了解，并刺激仿生工程和机器人技术。结合三维飞行路径跟踪、呼叫分析、回放实验和空间建模，我将研究蝙蝠如何跟随、逃避和相互交流（“空中交通管制”），以及这如何影响蝙蝠群体的紧急空间模式。我将量化多个自由放养的蝙蝠在不同飞行情况下的飞行轨迹和个体间反应，并将它们的飞行行为与发出的叫声联系起来。不同物种和不同距离的回声定位和社会呼叫回放将测试对飞行方向、轨迹测量和多个个体整体空间利用的种间和距离依赖效应。在运动生态学的框架下，我将使用获得的数据来开发随机状态空间模型，并测试跟随和逃避飞行的行为规则。因此，我的目标是实现一种基于机制的理解，即个体的声音和逃跑行为如何影响其他个体的逃跑和整个群体的涌现模式。

Communication and movement are crucial behaviours that enable social interactions between animals. In echolocating bats, communication and movement are naturally coupled: during flight, bats ‘communicate with themselves’ by listening for echoes of their own powerful calls. This constant stream of calls is also audible to other bats and informs them about the sender`s position and behaviour. Besides echolocation calls, bats also emit a variety of social calls during flight for interindividual communication. These two acoustic behaviours render bats the most vocal of mammals; their acoustic communication networks during flight are dense, spatio-temporally dynamic and involve diverse acoustic stimuli, often from different species. Echolocating bats are thus ideal to reveal evolution-tested communication and navigation strategies, which will advance our insight into behavioural principles and stimulate bio-inspired engineering and robotics.Combining three-dimensional flight path tracking, call analysis, playback experiments and spatial modelling, I will study how bats follow, evade and communicate with each other (‘air traffic control’) and how this affects the emergent spatial patterns of bat groups. I will quantify flight trajectories and inter-individual reactions of multiple free-ranging bats in different flight situations and relate their flight behaviour to emitted calls. Playbacks of echolocation and social calls of different species and from different distances will test for interspecific and distance-dependent effects on flight direction, trajectory measures and overall space use of multiple individuals. In a framework of movement ecology, I will use the obtained data to develop stochastic state-space models and to test behavioural rules for following and evasion flight. I thus aim to achieve a mechanism-based understanding of how individual vocal and flight behaviour affects the flight of other individuals and the emergent patterns of whole groups.