Listeners to a person letting loose with a roar can accurately estimate the size and formidability or the human noise maker.

细听一个人咆哮，可以准确地估计出体型大小和危险性，或者鉴别发出声音的是谁。

撰文播音：克里斯托弗·因塔利亚塔（Christopher Intagliata）

翻译：陈美娟

审校：潘磊

【狮吼声】

The animal kingdom is full of species that use sound—growls and bellows and roars—to signal size. Dogs do it. Red deer do it. Koalas do it.

动物世界中，叫声常常被用来表明自身体型的大小——例如咆哮、低鸣、怒吼。狗会这么叫（狗吠）。红鹿会这么叫（鹿鸣）。考拉会这么叫（考拉咕噜声）。

But now we can add humans to that list. Because a new study suggests we can size up other people by  the sound of their roar alone.

而现在，我们可以把人类也算进这个名单里（人类的吼叫），因为最新研究表明我们可以通过吼叫声鉴别他人的体型。

First, researchers took the circumference of 61 men's and women's biceps, measured their grip strength, and their height. Then they told 'em to let loose a roar.

研究者实验了男性和女性共61人，测定二头肌的大小、握力以及他们的身高。然后记录每个人吼叫的声音。

"I would probably describe it as the most hellish version of Groundhog Day you can think of." Jordan Raine, a behavioral ethologist at the University of Sussex. "If you just imagine 30 actors in training coming into a small room one after another and roaring at you, um, yeah it was an experience, that's for sure." 

“我想说，一遍遍听每个人的吼叫就像在经历地狱版本的土拨鼠日。”来自瑟赛克斯大学的行为学家约旦·雷恩这么说道。“嗯，这种感觉就像是，你可以想象30个正受训练的演员一个接一个进入这个小房间，然后每个人开始对着你嘶吼。”

His team then played those roars back to a separate group of male and female listeners, who'd also been measured for strength and size. They found that men correctly rated other men as substantially stronger than them 90 percent of the time, based on roar alone.

他的团队将这些吼叫声播放给另一组人听，他们也都被测量了握力和体型数据。研究者发现，男性能仅仅通过吼叫声准确地辨别比自身力气大的男性，准确率达到了90%。

Men did tend to underestimate women's strength by the sound of their roars, overestimated men's strength. But, in general, roaring like a wild animal seemed like a pretty accurate way to telegraph body size and strength.

另一方面，他们却容易从嘶吼声中低估女性的力量，而女性往往会高估男性的力量。但通常来说，通过野生动物一样的吼声似乎是一个颇为精准的描述体型和力量的办法。

The researchers also found that regular shouting  did not seem to have the same effect as a roar. "So what the roaring is actually doing is having this exaggerating effect on strength, which is very similar to the adaptations that non-human mammals possess that allow them to exaggerate their strength as well." The full results—and more roars—are in the journal  iScience. [Jordan Raine et al., Human Listeners Can Accurately Judge Strength and Height Relative to Self from Aggressive Roars and Speech]

研究者也发现，普通的大叫声（大叫声）并不能起到和吼声一样的效果。“吼声能显示个体力量，这与人以外的哺乳动物对力量的炫耀非常相似。”所有研究结果及更多对吼叫的研究都刊登在iScience杂志中。

The finding could have practical, real-world applications too. For example, soldiers have roared in battle throughout history to attempt to intimidate the enemy. "And the U.S. National Park Service actually recommends roaring as a defense strategy against bears."

相关研究成果在现实生活中还可能有更多应用。例如，历史上就有士兵用吼叫声威慑敌人的案例。另外，美国国家公园管理局倾向使用吼叫声作为一种防御熊类袭击的方法。

Just hope that the bears' hearing is better than their eyesight. 

希望熊的听力能比它的视力更好吧。