Graduate School of Informatics, Kyoto University, Engineering Building #10, Sakyo, Kyoto 606-8501, Japan.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2011 Sep;197(9):915-21. doi: 10.1007/s00359-011-0652-7. Epub 2011 May 15.
We present a novel method for imaging acoustic communication between nocturnal animals. Investigating the spatio-temporal calling behavior of nocturnal animals, e.g., frogs and crickets, has been difficult because of the need to distinguish many animals' calls in noisy environments without being able to see them. Our method visualizes the spatial and temporal dynamics using dozens of sound-to-light conversion devices (called "Firefly") and an off-the-shelf video camera. The Firefly, which consists of a microphone and a light emitting diode, emits light when it captures nearby sound. Deploying dozens of Fireflies in a target area, we record calls of multiple individuals through the video camera. We conduct two experiments, one indoors and the other in the field, using Japanese tree frogs (Hyla japonica). The indoor experiment demonstrates that our method correctly visualizes Japanese tree frogs' calling behavior. It has confirmed the known behavior; two frogs call synchronously or in anti-phase synchronization. The field experiment (in a rice paddy where Japanese tree frogs live) also visualizes the same calling behavior to confirm anti-phase synchronization in the field. Experimental results confirm that our method can visualize the calling behavior of nocturnal animals in their natural habitat.
我们提出了一种新的方法来对夜间动物的声通讯进行成像。由于需要在嘈杂的环境中区分许多动物的叫声而无法看到它们，因此研究夜间动物（例如青蛙和蟋蟀）的时空叫声行为一直具有挑战性。我们的方法使用数十个声-光转换设备（称为“萤火虫”）和现成的摄像机来可视化空间和时间动态。萤火虫由麦克风和发光二极管组成，当它捕获附近的声音时会发光。在目标区域中部署数十个萤火虫，我们通过摄像机记录多个个体的叫声。我们进行了两项实验，一项在室内，另一项在野外，使用日本树蛙（Hyla japonica）。室内实验表明，我们的方法可以正确地可视化日本树蛙的叫声行为。它证实了已知的行为，即两只青蛙同步或反相同步地鸣叫。野外实验（在日本树蛙生活的稻田中）也可视化了相同的叫声行为，以确认野外的反相同步。实验结果证实，我们的方法可以在自然栖息地中可视化夜间动物的叫声行为。
