Musical Pitch Perception May Have Long Evolutionary History
音感可能是长期进化的结果

A tiny primate, the marmoset, appears to process pitch perception the same way we do, implying that the ability evolved in a common ancestor at least 40 million years ago
狨猴，一种小型的灵长类动物，和我们一样具有音感。这暗示着这种能力或许可追溯到
4000万年前我们共同的祖先。

撰文/播音 克里斯汀·赫尔曼 (Christine Herman)
翻译 Meatle
审校 乔虹

The ability to distinguish between sounds of varying pitch makes people capable of producing and understanding speech and music. And the way we are able to process pitch has been thought to be unique to our big-brained species.
 得益于分辨多种音调的能力，人类能够创作与欣赏演讲和音乐。这种能够处理音调的能力通常被认为是脑部发达的物种所特有的。

But now, there’s evidence that a tiny monkey—the common marmoset from Brazil—can distinguish pitch the same way we do. That’s according to a study in the Proceedings of the National Academy of Sciences. [Xindong Song et al, Complex pitch perception mechanisms are shared by humans and a New World monkey]
 然而现在，有证据表明一种体型娇小的猿类，巴西的狨猴，能像我们一样分别出音调。这个结论来自《美国科学院论文集》（Proceedings of the National Academy of Sciences.）上的一项研究。[Xindong Song et al, Complex pitch perception mechanisms are shared by humans and a New World monkey]

Ten years ago, researchers identified a region of the marmoset brain that appeared to process pitch. But they needed to confirm that the animals did indeed notice changes in pitch—which presented a challenge: they had to find a way to get the animal to indicate that it had heard something. So they trained the marmosets to respond to a change in pitch with a behavior—specifically, they would lick a waterspout.
 十年前，研究人员识别出狨猴大脑中一个像是用于处理音调信息的区域。然而他们需要确认这种动物确实能够注意到音调的变化，而这正是困难所在：他们需找到一种方法，能让动物把它们听到的东西表达出来。因此，他们训练狨猴对音调的变化做出行为上的响应——具体来说，这些猴子会去舔排水口。

The researchers then had the animals listen to a series of notes with the same pitch. And, at random, they’d change it up. “Just like, for example, when I say, ‘ma ma ma MA.’ Right, at some point I make the pitch a little higher.” Johns Hopkins neuroscientist Xiaoqin Wang, lead researcher of the study. The actual difference in pitch, he says, was much smaller than that. But you get the idea. “And, when the animal hears that change, it will lick the waterspout to indicate they hear the difference.” Which the miniscule monkeys indeed did.
 之后，研究人员让狨猴去听一系列在同一音调上的音符。进而，随机地改变这些音符的音调。“例如，当我说‘ma ma ma MA’时，我们会在某些地方将音调调高一点。”该项研究的领导者，约翰斯·霍普斯金大学的神经学家王晓庆 (音译，Xiaoqin Wang) 解释道。不过他也说，实际上的音调变化比上面的例子还要微小。这只是让你明白这个概念。“而当狨猴听到了这些变化，它会舔排水口表示它听到了变化。”这些小猴子确实是这样做了。

Because both we and marmosets have this talent, the ability likely evolved in a common ancestor long-ago—this type of pitch perception may thus go back more than 40 million years ago, much earlier than previously thought. And the understanding of how the brain processes pitch may eventually explain why some people have perfect pitch, while others are tone deaf.
 因为我们和狨猴都拥有这种天赋，所以它很可能来自我们古老的共同祖先。这种音感能力也许能追溯到4000万年前，远比我们之前想象更早。对大脑如何处理音调进行深入的了解也许最终能帮我搞清楚为何一些人具有绝对音感，而另外一些则是五音不全。