Philosophical Transactions of the Royal Society B: Biological Sciences ( IF 6.3 ) Pub Date : 2021-09-06 , DOI: 10.1098/rstb.2021.0046 Julie N Oswald 1 , Sam F Walmsley 1 , Caroline Casey 2 , Selene Fregosi 2 , Brandon Southall 2, 3 , Vincent M Janik 1
The most flexible communication systems are those of open-ended vocal learners that can acquire new signals throughout their lifetimes. While acoustic signals carry information in general voice features that affect all of an individual's vocalizations, vocal learners can also introduce novel call types to their repertoires. Delphinids are known for using such learned call types in individual recognition, but their role in other contexts is less clear. We investigated the whistles of two closely related, sympatric common dolphin species, Delphinus delphis and Delphinus bairdii, to evaluate species differences in whistle contours. Acoustic recordings of single-species groups were obtained from the Southern California Bight. We used an unsupervised neural network to categorize whistles and compared the resulting whistle types between species. Of the whistle types recorded in more than one encounter, 169 were shared between species and 60 were species-specific (32 D. delphis types, 28 D. bairdii types). Delphinus delphis used 15 whistle types with an oscillatory frequency contour while only one such type was found in D. bairdii. Given the role of vocal learning in delphinid vocalizations, we argue that these differences in whistle production are probably culturally driven and could help facilitate species recognition between Delphinus species.
This article is part of the theme issue ‘Vocal learning in animals and humans’.
中文翻译:
普通海豚哨声频率调制模式中的物种信息
最灵活的交流系统是开放式声乐学习者的交流系统,它们可以在他们的一生中获得新的信号。虽然声学信号在影响个人所有发声的一般语音特征中携带信息,但声乐学习者也可以将新的呼叫类型引入他们的曲目。Delphinids 以在个体识别中使用这种学习的呼叫类型而闻名,但它们在其他情况下的作用不太清楚。我们调查了两种密切相关的同域常见海豚物种Delphinus delphis和Delphinus bairdii的哨声,以评估哨子轮廓的物种差异。从南加州湾获得了单一物种群的声学记录。我们使用无监督的神经网络对哨声进行分类,并比较了物种之间产生的哨声类型。在不止一次遭遇中记录的哨子类型中,169 种在物种之间共享,60 种是物种特异性的(32 种D. delphis类型,28 种D. bairdii类型)。Delphinus delphis使用了 15 种具有振荡频率轮廓的哨子类型,而在D. bairdii 中仅发现了一种这样的类型. 鉴于声音学习在海豚发声中的作用,我们认为口哨产生的这些差异可能是文化驱动的,可能有助于促进海豚物种之间的物种识别。
这篇文章是主题问题“动物和人类的声音学习”的一部分。