在线英语听力室

科学美国人60秒 SSS Red-Winged Blackbirds Understand Yellow Warbler Alarms

时间:2020-05-06 08:38:24

搜索关注在线英语听力室公众号:tingroom,领取免费英语资料大礼包。

(单词翻译)

Researchers studying yellow warbler responses to the parasitic1 cowbird realized that red-winged blackbirds were eavesdropping3 on the calls and reacting to them, too.

Full Transcript4 

Brown-headed cowbirds are obligate brood parasites5. That means they lay their eggs in the nests of other birds, leaving all the hard work of incubating the eggs and feeding the chicks to somebody else. Luckily, many of those other species have evolved some antiparasitic defenses. Yellow warblers, for example, produce a certain type of call to warn other warblers about nearby cowbirds. Researchers call it a “seet” call.

“We were working on the yellow warbler. And whenever we were doing seet call playbacks to the yellow warblers, the red-winged blackbirds kept showing up. That was truly a discovery, this aha moment that allowed us to explore this question even further.”

Ecologist Mark Hauber from the University of Illinois at Urbana-Champaign, who ran the study.

The yellow warblers’ seet call is called a “referential alarm call,” because it is only produced for a single threat: the brown-headed cowbird.

“And in response to the seet call, the female yellow warbler, instead of attacking or mobbing the cowbird, she sneaks6 back to her nest and sits on it tightly so as to prevent the cowbird from being able to lay a parasitic egg.”

Red-winged blackbirds, which sometimes nest near warblers, do not produce referential alarm calls. But it turns out that they can eavesdrop2 on the yellow warblers’ calls. And they respond to the seet calls the same way they do to the sounds of cowbirds themselves. The results were published in the journal Communications Biology. [Shelby L. Lawson et al., Heterospecific eavesdropping on an anti-parasitic referential alarm call]

So red-winged blackbirds prefer to nest near yellow warblers, since the warblers provide additional vigilance against brown-headed cowbirds. But it’s probably a two-way street.

“From the literature, we know that yellow warblers do better when they nest near red-winged blackbird territories. And that makes sense because the redwings are really aggressive. If you walk in a reed bed full of redwings, you actually get physically7 attacked by the redwings. They are not intimidated8 by large predators9. So for the yellow warblers, it makes sense for them to nest near the redwings.”

The researchers say that this is the first known evidence of animals eavesdropping on antiparasitic referential alarm calls.

“These birds, yellow warblers and red-winged blackbirds, they speak different languages. They understand their own communication signals and systems. And what we discovered here is, basically, a bilingual red-winged blackbird that can understand the vocalization systems and the communication systems of another species.”

Young birds learn their vocalizations much like young humans learn languages. In future research, Hauber hopes to understand whether the birds rely on the same underlying10 neurobiology to understand the calls of other species as they do when they hear the sounds of their own species—and what that might mean for our own efforts to learn additional languages.

—Jason G. Goldman

[The above text is a transcript of this podcast.]


分享到:


点击收听单词发音收听单词发音  

1 parasitic 7Lbxx     
adj.寄生的
参考例句:
  • Will global warming mean the spread of tropical parasitic diseases?全球变暖是否意味着热带寄生虫病会蔓延呢?
  • By definition,this way of life is parasitic.从其含义来说,这是种寄生虫的生活方式。
2 eavesdrop lrPxS     
v.偷听,倾听
参考例句:
  • He ensconced himself in the closet in order to eavesdrop.他藏在壁橱里,以便偷听。
  • It is not polite to eavesdrop on the conversation of other people.偷听他人说话是很不礼貌的。
3 eavesdropping 4a826293c077353641ee3f86da957082     
n. 偷听
参考例句:
  • We caught him eavesdropping outside the window. 我们撞见他正在窗外偷听。
  • Suddenly the kids,who had been eavesdropping,flew into the room. 突然间,一直在偷听的孩子们飞进屋来。
4 transcript JgpzUp     
n.抄本,誊本,副本,肄业证书
参考例句:
  • A transcript of the tapes was presented as evidence in court.一份录音带的文字本作为证据被呈交法庭。
  • They wouldn't let me have a transcript of the interview.他们拒绝给我一份采访的文字整理稿。
5 parasites a8076647ef34cfbbf9d3cb418df78a08     
寄生物( parasite的名词复数 ); 靠他人为生的人; 诸虫
参考例句:
  • These symptoms may be referable to virus infection rather than parasites. 这些症状也许是由病毒感染引起的,而与寄生虫无关。
  • Kangaroos harbor a vast range of parasites. 袋鼠身上有各种各样的寄生虫。
6 sneaks 5c2450dbde040764a81993ba08e02d76     
abbr.sneakers (tennis shoes) 胶底运动鞋(网球鞋)v.潜行( sneak的第三人称单数 );偷偷溜走;(儿童向成人)打小报告;告状
参考例句:
  • Typhoid fever sneaks in when sanitation fails. 环境卫生搞不好,伤寒就会乘虚而入。 来自《简明英汉词典》
  • Honest boys scorn sneaks and liars. 诚实的人看不起狡诈和撒谎的人。 来自辞典例句
7 physically iNix5     
adj.物质上,体格上,身体上,按自然规律
参考例句:
  • He was out of sorts physically,as well as disordered mentally.他浑身不舒服,心绪也很乱。
  • Every time I think about it I feel physically sick.一想起那件事我就感到极恶心。
8 intimidated 69a1f9d1d2d295a87a7e68b3f3fbd7d5     
v.恐吓;威胁adj.害怕的;受到威胁的
参考例句:
  • We try to make sure children don't feel intimidated on their first day at school. 我们努力确保孩子们在上学的第一天不胆怯。
  • The thief intimidated the boy into not telling the police. 这个贼恫吓那男孩使他不敢向警察报告。 来自《简明英汉词典》
9 predators 48b965855934a5395e409c1112d94f63     
n.食肉动物( predator的名词复数 );奴役他人者(尤指在财务或性关系方面)
参考例句:
  • birds and their earthbound predators 鸟和地面上捕食它们的动物
  • The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》
10 underlying 5fyz8c     
adj.在下面的,含蓄的,潜在的
参考例句:
  • The underlying theme of the novel is very serious.小说隐含的主题是十分严肃的。
  • This word has its underlying meaning.这个单词有它潜在的含义。

本文本内容来源于互联网抓取和网友提交,仅供参考,部分栏目没有内容,如果您有更合适的内容,欢迎 点击提交 分享给大家。