一項研究說，瓶鼻海豚在自然交流期間能夠使用有特徵的口哨與社會同伴打交道。在模仿環境中的聲音從而發展出獨特的呼叫的動物中間，鸚鵡和海豚最突出，因為它們在實驗環境下具有使用學到的信號命名物體的能力。為了確定這種能力是不是瓶鼻海豚自然交流系統的一部分，Stephanie King 和Vincent Janik檢驗了海豚是否使用有特徵的口哨——獨立於語音的呼叫，對於個體是獨特的，並且這些動物在海中相遇的時候會互相呼喚——用於與個體打交道。這組作者跟蹤了蘇格蘭沿海東部的一個野生的、自由生活的海豚種群，監測了它們對不同口哨的反應。這組科研人員或者回放記錄下來的一隻海豚自己的有特徵的口哨的一個合成版本，或者回放來自同一個種群的熟悉的海豚的口哨，或者來自不同種群的不熟悉的海豚的口哨。野生瓶鼻海豚通過應答呼叫從而對它們自己的特徵口哨做出反應，但是它們對其他的口哨沒有做出反應。這組作者說，這些發現提示海豚可能使用有特徵的口哨作為標籤從而與同一物種的個體打交道或者進行接觸，而且對身份信號的使用類似於人類命名個體的習慣。（生物谷 Bioon.com）
生物谷推薦的英文摘要
PNAS doi: 10.1073/pnas.1304459110
Bottlenose dolphins can use learned vocal labels to address each other
Stephanie L. King and Vincent M. Janik
In animal communication research, vocal labeling refers to incidents in which an animal consistently uses a specific acoustic signal when presented with a specific object or class of objects. Labeling with learned signals is a foundation of human language but is notably rare in nonhuman communication systems. In natural animal systems, labeling often occurs with signals that are not influenced by learning, such as in alarm and food calling. There is a suggestion, however, that some species use learned signals to label conspecific individuals in their own communication system when mimicking individually distinctive calls. Bottlenose dolphins (Tursiops truncatus) are a promising animal for exploration in this area because they are capable of vocal production learning and can learn to use arbitrary signals to report the presence or absence of objects. Bottlenose dolphins develop their own unique identity signal, the signature whistle. This whistle encodes individual identity independently of voice features. The copying of signature whistles may therefore allow animals to label or address one another. Here, we show that wild bottlenose dolphins respond to hearing a copy of their own signature whistle by calling back. Animals did not respond to whistles that were not their own signature. This study provides compelling evidence that a dolphin’s learned identity signal is used as a label when addressing conspecifics. Bottlenose dolphins therefore appear to be unique as nonhuman mammals to use learned signals as individually specific labels for different social companions in their own natural communication system.