Ou Wenzhan, Song Zhongchang, Goertz Caroline E C, Mooney T Aran, Dennison Sophie, Zhang Chuang, Zhang Yu, Castellote Manuel
College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, People's Republic of China.
Alaska SeaLife Center, Seward, AK 99664, United States of America.
Bioinspir Biomim. 2025 Apr 4;20(3). doi: 10.1088/1748-3190/adc5bd.
The biosonar system of odontocetes enables directional sound transmission and reception. Beluga whales () are notable among odontocetes as they can alter the shape of their fatty melon during sound transmission, potentially suggesting distinct acoustic capabilities. In this study, we developed a biosonar model of a beluga whale using computed tomography scanning and structural reconstruction to examine directional transmission and reception in this species. This model could modulate sounds into a directional beam using either single or dual sources. Across frequencies from 5 to 60 kHz, the directivity indices for the left and right sound sources ranged from 4.83 to 15.2 dB and 4.81-14.7 dB, respectively. When both sound sources were used simultaneously, there was an average increase of at least 2.26 dB in energy and 0.68 dB in the directivity index compared to using a single source. Additionally, beam steering was achieved in the dual-source transmission by introducing a timing difference between the two sources. The simulations indicated that sound reception was frequency-dependent, with the greatest sensitivity to lateral sounds at low frequencies and to forward sounds at high frequencies. These results suggested that both transmission and reception in beluga whales were directional and frequency-dependent.
齿鲸的生物声纳系统能够实现定向的声音传播与接收。白鲸（）在齿鲸中较为显著，因为它们在声音传播过程中能够改变其脂肪质的额隆形状，这可能暗示着其独特的声学能力。在本研究中，我们利用计算机断层扫描和结构重建技术开发了白鲸的生物声纳模型，以研究该物种的定向传播与接收。该模型能够使用单源或双源将声音调制为定向波束。在5至60千赫的频率范围内，左右声源的指向性指数分别为4.83至15.2分贝和4.81至14.7分贝。当同时使用两个声源时，与使用单个声源相比，能量平均至少增加2.26分贝，指向性指数平均增加0.68分贝。此外，通过在两个声源之间引入时间差，在双源传输中实现了波束控制。模拟结果表明，声音接收与频率相关，在低频时对侧向声音最敏感，在高频时对前方声音最敏感。这些结果表明，白鲸的声音传播和接收都是定向的且与频率相关。
