松鼠依赖鸟类让它们知道什么时候出去是安全的

松鼠依赖鸟类让它们知道什么时候出去是安全的

Never underestimate a squirrel's survival skills.

永远不要低估松鼠的生存技能。

Gifted acrobats, they trampoline from tree to tree, always a step ahead of danger. They've even been known to gather old rattlesnake skins and rub the scent on their fur to create a kind of predator repellant.

有天赋的杂技演员，他们从一棵树跳到另一棵树，总是走在危险的前面。人们甚至知道它们会收集旧的响尾蛇皮，把气味涂抹在它们的皮毛上，制造出一种捕食者驱虫剂。

Photo: KellyNelson/Shutterstock

And now, a newly published study in the journal Plos One suggests squirrels rely on social media to figure out when it's safe to leave home: they read tweets.

现在，发表在《公共科学图书馆•综合》(Plos One)杂志上的一项最新研究表明，松鼠依靠社交媒体来判断什么时候离开家是安全的:它们会阅读推特。

As in, actual chirps and chatter from songbirds in the neighborhood.

就像附近鸣禽的叫声一样。

No, for all their incredible abilities, squirrels don't actually speak the language of birds. Rather, researchers from Ohio's Oberlin College suggest, they keep their ears to the ground — and try to get the gist of a conversation.

不，尽管松鼠拥有令人难以置信的能力，但它们实际上不会说鸟类的语言。相反，来自俄亥俄州奥伯林学院的研究人员建议，它们保持耳朵贴近地面，努力抓住谈话的要点。

What's all that chirping about outside, a wary squirrel might ask himself? Did someone just say, "red-tailed hawk?"

一只警惕的松鼠可能会问自己，外面到底在唧唧叫些什么?是不是有人说"红尾鹰" ?"

Better to curl up in the burrow until things settle down out there.

最好蜷缩在洞穴里，直到外面的一切都安定下来。

"This study suggests that eavesdropping on public information about safety is more widespread and broader than we originally thought," study co-author Keith Tarvin tells The Guardian.

“这项研究表明，窃听有关安全的公共信息比我们最初认为的更广泛，范围更广，”研究合著者基思·塔文告诉《卫报》。

Indeed, songbirds don't owe grey squirrels anything. Neither species is dependent on the other, the researchers note, and they move from place independently, But when squirrels happen to have birds as neighbors, they make savvy use of their chatter.

事实上，鸣禽并不欠灰松鼠任何东西。研究人员指出，这两种动物都不依赖于另一种，它们从一个地方搬到另一个地方是独立的，但当松鼠碰巧有鸟类为邻时，它们会巧妙地利用它们的叫声。

"It may not require tight ecological relationships that allow individuals to carefully learn the cues provided by other species," Tarvin adds.

“它可能不需要紧密的生态关系，让个体仔细学习其他物种提供的线索，”塔尔文补充说。

For the study, researchers looked at a 67 grey squirrels going about their nut-gathering business around the city of Oberlin. After observing them for a period, the team played a short clip of a red-tailed hawk's call. Predictably, the squirrels got really nervous, freezing in place — a typical defense strategy among rodents — and looking up to the sky for signs of dive-bombing death.

在这项研究中，研究人员观察了67只灰松鼠，它们在奥伯林市周围从事采集坚果的工作。在观察了一段时间后，研究小组播放了一段红尾鹰叫声的短片段。不出所料，松鼠变得非常紧张，原地不动——啮齿动物的典型防御策略——它们抬头仰望天空，寻找俯冲轰炸致死的迹象。

Then the scientists played a clip of songbirds chatting normally. And sure enough, the squirrels went back to their foraging ways — as if to say, if it's safe enough for birds, it's safe enough for us.

然后，科学家们播放了一段鸣禽正常交谈的视频。果然，松鼠们又开始了它们的觅食之路——仿佛在说，如果对鸟类来说够安全，对我们来说也够安全。

The findings seem to be in keeping with a squirrel's abiding philosophy of letting others do most of the work for them. By letting birds shoulder all the anxiety of a potential threat, squirrels can focus their energy on their one great obsession: nut acquisition.

这一发现似乎符合松鼠一贯的哲学，即让别人为自己做大部分工作。通过让鸟类承担所有潜在威胁的焦虑，松鼠可以把它们的精力集中在它们最大的痴迷上:获取坚果。

"Recognition of bird chatter as a sign of safety is likely adaptive, as squirrels that can safely reduce their vigilance level in the presence of bird chatter presumably are able to increase foraging success," the researchers noted in the study.

研究人员在研究中指出:“将鸟类的鸣叫作为安全信号的识别可能是适应性的，因为在鸟类鸣叫的存在下，松鼠可以安全地降低警惕水平，这可能会提高觅食的成功率。”

Indeed, life in the forest, or even the lone tree in your backyard, isn't all nuts and honey. Snakes, coyotes, hawks and owls are constantly on the prowl for wayward rodents. And constantly fretting about them can be taxing on a squirrel.

事实上，森林里的生活，甚至是你后院唯一的一棵树，并不都是坚果和蜂蜜。蛇、土狼、鹰和猫头鹰一直在寻找任性的啮齿动物。对松鼠来说，不停地为它们烦恼是一种负担。

Best, it seems, to let birds handle the Neighborhood Watch.

最好的办法似乎是让鸟类来处理邻里监督。