Animals with complicated fluid social systems exchange individualized contact calls to maintain relationships. Studies on bottlenose dolphins over the past 50-years have revealed that their contact calls, also known as ‘signature whistles’, were similar to the form of ‘names’ in humans.
Bottlenose dolphins have individually distinctive frequency modulation patterns insignature whistles。身份信息independent of voice cues, and the individual pattern wasobtained by vocal learning。Further, dolphinscopy the signature whistles of group membersand使用它们标记特定的小组成员。
This type of contact call was found in only bottlenose dolphins anda parrot species除了人类。为什么这些物种获得了名称？个体识别系统如何发展？我们有兴趣找出这种类型的接触呼叫是否是这些物种独有的，特别是其他齿鲸是否会产生这种类型的接触呼叫。
More about beluga whales
They may integrate these skills into an individual recognition system of contact calls akin to that in bottlenose dolphins.
Beluga whales are a circumpolar and annual-migratory species. They have similar fluid social structure to bottlenose dolphins. Thus we expect that they use individually distinctive contact calls. Further, they mimichuman speechandsynthetic sounds, and canlabel objects using sounds。Thus, they may integrate these skills into an individual recognition system of contact calls akin to that in bottlenose dolphins.
蓝宝石被称为“海洋金丝雀”，它们会产生各种电话。尽管对贝鲁加斯的接触电话知之甚少，但过去的一些研究报告说他们used pulsed soundswhich were the other type of two widely categorized call types in toothed whales, rather than whistles for母亲接触电话。
Previously, Dr. Morisaka and his colleagues suggestedindividuality in contact calls of belugas.They reported that belugas frequently exchanged one type of individualized pulsed sound, called ‘PS1’. However, only a small amount of data was analyzed in a short period.
Therefore we conducted a subsequent investigation of PS1 to evaluate its function as a contact call and individuality. This is the first step in assessing whether PS1 calls have a parallel function to signature whistles in bottlenose dolphins.
What did we do?
Recordings were conducted on each of five belugas at the Port of Nagoya Public Aquarium in Japan, including both sexes and various ages. We separated each animal into a sub-pool and made an isolated context to elicit contact calls from them.
结果，PS1是最常见的隔离呼叫类型，该呼叫类型表明PS1充当接触呼叫。另外，一名亚成年和三个成年人在PS1中具有单独的独特和定型的脉搏重复模式。一只小腿没有明确的刻板印象重复模式。
上图显示了来自五个白鲸的PS1样品。您可以从否中听到PS1电话。1至否。5。here。PS1 is not a beautiful sound in contrast to whistles and it sounds like a door creaking to human ears, although we can hear a part of PS1 because it contains the ultrasonic component (>20 kHz).
对于人类而言，样本之间的脉冲重复模式的差异可能不清楚，但是贝鲁加斯可能会清楚地认为它们的听觉系统具有比人类更高的时间分辨率。
What did we find?
The findings mean that belugas use PS1 as an individualized contact call. If belugas encode signature information in PS1 calls, as seen in bottlenose dolphins, the pulse repetition pattern may be the carrier, as it is individually stereotyped and appears to require vocal development.
The next step is playback experiments to elucidate whether the individual differences were perceived by belugas, and whether the pulse repetition pattern functions as a signature.
Comments