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This is Scientific American's 60-second Science, I'm Annie Sneed.

这里是科学美国人——60秒科学系列，我是安妮·斯尼德。

The beak¹ shapes of different species of Galapagos finches played an important part in Darwin's conception of natural selection.

加拉帕戈群岛不同雀类的鸟喙形状在达尔文的自然选择学说中扮演了重要角色。

"In our field there is this presumption² that the beak shape ... in birds is quite correlated with what they eat and how they eat it—so, their feeding ecologies."

“我们的研究领域存在这样一种假设：鸟喙形状与其食物及进食方式息息相关，也就是与它们的摄食生态有关。”

Guillermo Navalón, a PhD student at the University of Bristol in the U.K. and a co-author of a new study that found that the connection between beak shape and diet isn't as tight as we thought. The study is in the journal Evolution.

英国布里斯托尔大学的博士生吉尔莫·纳瓦隆说到，他也是一项新研究的作者之一，该研究发现，鸟喙形状与饮食之间的联系并不像我们我们想象的那样紧密。这项研究发表在《进化》期刊上。

Navalón and his colleagues analyzed³ photographs of museum specimens⁴ of 176 bird skulls⁵. They looked at beak shape and size in almost all of the orders of modern birds and compared the beaks⁶ with other factors, such as feeding behavior and body size. And they found that the beak shape was indeed somewhat tied to what birds feed on and how they eat it—but the relationship was actually surprisingly weak, accounting⁷ for just 12 percent of beak shape variation.

纳瓦隆和同事分析了博物馆中176个鸟类头骨标本的照片。他们研究了几乎所有现代鸟的鸟喙形状和大小，并将鸟喙与摄食行为及体型大小等其它因素进行了比较。他们发现，鸟喙形状的确在某种程度上与鸟类的饮食和进食方式有关——但这种关联实际上出奇地微弱，只在鸟喙形状变化因素中占12%。

"The explanation that we extract from there is that the beaks are basically surrogate hands in the birds. They are used for a plethora⁸ of different functions beyond feeding ecology. Like the beak in general in birds have many other functions, so they use it for display, nest construction, singing, thermoregulation in some cases like toucans⁹ or like hornbills ... so there is like a lot of factors that probably have intervened in the evolution of beaks in birds."

“我们从中获得的解释是，鸟喙基本上是鸟类的‘替代手’。除了摄食生态之外，鸟喙还有其它多种用途。正如鸟喙通常还有许多其它功能一样，鸟会用鸟喙来进行展示、筑巢、唱歌，巨嘴鸟或犀鸟等也会用鸟喙来调节温度，因此，可能有许多因素干预了鸟喙的进化。

Thanks for listening for Scientific American — 60-Second Science. I'm Annie Sneed.