Feathers are not just for flight. They keep birds warm, become part of their nests, and help them attract mates. And for one Australian bird, feathers even help produce an important sound—an alarm.

　　羽毛并不仅仅是用于飞行。羽毛可以帮助鸟类保暖、做巢并帮助它们吸引异性。而对于一种澳大利亚鸟类来说，羽毛甚至可以帮助制造一种重要的声音-警报。

　　“People had long noticed that these birds produced these loud whistles.”

　　很久以前人们就注意到这些鸟类可以发出响亮的口哨声。

　　Trevor Murray, a postdoctoral researcher at the Australian National University.

　　特雷弗.默里是澳大利亚国立大学的博士后研究员。

　　“My supervisor Rob Magrath in collaboration with May Hingee thought that they were used as an alarm. So they did some playbacks and they could show quite strongly that if you play back these sounds to other birds, they flee straightaway. So what I was really interested in was following up on that research and finding out how they produce the sound, whether it is actually a signal, and whether it’s a reliable signal.”

　　我的导师 Rob Magrath以及合作的同事May Hingee认为，鸟类将这种声音用作警报。所以他们对这些声音进行了回放。结果清晰地显示，如果将这些声音回放给其他的鸟儿，这些鸟儿会立刻逃跑。所以，我对后续的研究非常感兴趣并想查明这些鸟是如何发出这些声音，它是否是一个信号，抑或是一个可靠的信号。

　　The team focused their experiment on specific feathers in the crested pigeon’s wing. “We were able to target the eighth primary feather, which is unusually narrow—it’s about half the width of the surrounding feathers. And then we also removed, on different sets of birds, we also removed those neighboring feathers, the ninth primary feather and the seventh primary feather...and we were able to see…that the eighth primary feather, when it was missing, the high note had completely disappeared. So the eighth primary feather produced that high note and the ninth primary feather, it turns out, actually produced the low note.”

　　研究团队将实验重点放到冠状鸽子翅膀的特定的羽毛上。我们的研究对象是第八根主翼羽-异常狭窄，其宽度约是周围羽毛的一半。同时，我们才收集了不同鸟类的这种羽毛，并移除了其周围的羽毛，第9根主翼羽和第7根主翼羽……同时我们还了解到，当第8根主翼羽消失时，声音重的高音也就完全消失了。所以，第8根主翼羽制造高音，结果表明，第9根主翼羽负责制造低音。

　　And if the birds are fleeing from danger, they produce a louder and higher tempo whistle than they do during a normal takeoff. The study is in the journal Current Biology.

　　如果鸟类正在躲避危险，那么它们发出的声音比正常起飞时要更加响亮。该研究结果发表在《当代生物学》杂志上。

　　Murray and his colleagues did another experiment where they used the recordings they made to observe the reactions of other crested pigeons. “And from this experiment we were able to see that the eighth primary feather, the unusual feather, was actually crucial for signaling alarm. When that eighth primary feather was missing, they very rarely responded. They almost never fled.

　　默里和同事做了另一个实验。他们利用声音记录观察其他冠状鸽子的反应。“从这个实验中，我们知道第8根主翼羽，这根不同寻常的羽毛是发出警报声的关键。当没有第八根羽毛时，鸟类对于发生的声音没有反应。几乎鸟类都不会逃跑。”

　　Whereas when the neighboring feather that produces the other part of the sound, that ninth primary, they actually fled just as much as to normal alarms. This shows us that this unusual primary feather is crucial for signaling alarm, and together that suggests that it has evolved to communicate with its flock mates.”

　　但是，当邻近的羽毛，即第9根主翼羽，发出其他声音时，实际上，鸟类的逃跑跟听到正常的警报声差不多。这表明，这种不寻常的羽毛对于发出警报是至关重要的，同时也表明它已经进化到与其他同伴进行交流了。”

　　So that birds of a feather can flee together.

　　所以啊，同甘共苦(有羽毛的鸟可以一起逃跑~)。