Bats are sophisticated communicators. And not just when they’re in vampire form. New research finds that Egyptian fruit bats actually have regional dialects, depending on the bat chatter that surrounds them as they grow up. The study is in the journal PLOS Biology.

蝙蝠都是“交流大师”，这里所说的蝙蝠并不仅仅指吸血蝙蝠。一项新的研究发现，事实上，埃及果蝠间存在着方言，这种方言的形成取决于蝙蝠宝宝成长时周围蝙蝠所发出的声音。这项研究发表在《公共科学图书馆·生物学》杂志中。

撰文/播音：凯伦·霍普金

翻译：曲荟龙

审校：许楠

Among humans, one person’s howdy is another one’s g’day. Wild populations of bats also display group-specific vocalizations. But how do these vocal characteristics arise? Do they reflect innate, genetic differences or are they learned? And if bat accents are acquired, who are these furry fliers imitating? Their parents? Or their roost-mates?

人类社会中，有人会问候“你好啊”，有人会问候“吃了吗您”。野生蝙蝠种群中也存在有这种现象，即某个群体会呈现出特有的声音分化。但是这种现象是如何产生的呢?它反映的是先天的、遗传的差异？还是后天习得的差异?如果蝙蝠的叫声是通过后天学习而获得的，那么这些毛茸茸的小家伙们会模仿谁呢?它们的父母吗?还是与它们一起栖息的同伴们呢?

To find out, Yossi Yovall at Tel Aviv University and his colleagues captured 15 pregnant fruit bats and divided them into three groups, each of which was housed in its own separate box. The mothers gave birth inside these boxes and their babies, called pups, lived there for a full year. During that time, the researchers exposed the pups to a select symphony of bat sounds. Fruit bats in the wild are reared in colonies that contain dozens to thousands of individuals, so they’re used to being surrounded by a cacophony of calls and other vocal communiques.

为了寻找答案，以色列特拉维夫大学（Tel Aviv University）的约西·尤沃（Yossi Yovall）和他的同事们捕获了15只怀孕的果蝠，并将它们分成三组，每组分别放置在彼此分开的盒子中。母蝙蝠们在这些盒子中产下幼崽，并在这里生活整整一年。这段时间里，研究人员将蝙蝠幼崽们放置在特定的蝙蝠声音中。野生果蝠群包含有几十个甚至几千只不同的蝙蝠，因此果蝠幼崽已经习惯了周围存在着嘈杂的叫声或是其他的声音。

For one of the boxes, Yovall and his team exposed the young batlings to a selection of squeaks that were biased toward the higher frequencies. Pups in the second box heard lower-pitched peeps. And the third box got a random sampling of fruit bat hits that was heavy on the mid-range frequencies but also included those at either end of the aural spectrum.

尤沃及团队将第一个盒子里的蝙蝠幼崽放置在相对高频的蝙蝠声中，第二个盒子里的蝙蝠幼崽放置于相对低频的声音中。第三个盒子使用随机抽取的果蝠声音样本，这些样本以中等频率为主，但也包括了在听觉谱两端的声音。

“And what we found is that they were influenced by the playback that they heard.”Yossi Yovall.

“我们发现，果蝠幼崽会受它们所听的‘背景音’的影响。”约西·尤沃表示。

“So the control group was using a vocal repertoire that was identical to their mothers and identical to fruit bats in the colony here in Israel. But the two manipulated groups were using different dialects...we actually were able to create three different groups of fruit bats with three different dialects in the lab.”

“对照组使用与幼崽母亲完全相同的声音，这种声音和以色列当地的果蝠种群声音一致。但是在两个实验组中，我们使用的是与之不同的、果蝠间的‘方言’。实际上，我们在实验室里创造了三种不同的果蝠——它们拥有三种不同的方言。”

Of course, birds are famous for their songs. Which the males learn from tutors, typically their dads. But Yovall says when it comes to vocal learning, bats march to a different drummer.

我们都知道鸣叫是鸟类的‘特色’。雄鸟从它们的‘导师’那里学习鸣叫，而它们的导师通常是他们的父亲。但是尤沃认为，在鸣叫学习这一方面，蝙蝠和鸟类有所不同。

“Here we show that even though the pups were with their mothers, they were exposed to their mother’s normal repertoire, they were still influenced by the background vocalizations that they heard. Now this is probably extremely reasonable in the case of bats because bats roost in these caves with many hundreds of individuals…we believe that this process, which we call crowd vocal learning, because you learn from the entire crowd, is relevant for many other animals that live in crowded colonies.”

“我们的研究显示，尽管蝙蝠幼崽和它们的母亲生活在一起，会受到母亲叫声的影响，但同时也会受到背景声音的影响。在蝙蝠群中，这是一种极其合理的推断。因为蝙蝠和成百上千只同类共同栖息在洞穴中…我们将此称之为‘种群鸣叫学习’过程，因为幼崽会向整个种群学习,我们认为这个过程在许多其他生活在高密度群居种群中的生物中也存在。”

As the researchers note in their paper, this sort of social learning is sometimes called “culture.” Even if you’re living in a cave.

正如研究人员在他们的论文中指出的那样，这种社会性的学习有时被称为“文化”。即便是居住在山洞里的蝙蝠，这种文化依然存在。