But nobody had actually ever seen inside the throat of an animal as it vocalised.

但没人真正见过动物发声时其喉咙的状态。

They vocalised, tensed their muscles, arched their backs, and fussed or cried.

他们发出声，绷紧肌肉，弓起背，开或哭泣。

A baby vocalising will, at first, make a vowel-like sound, usually something like " ah" , which requires little in the way of control over the mouth.

婴儿发声一开会发出类似元的声，通常是“啊”之类的声，这几乎不需要控制嘴巴。

So what this is the larynx pulling down out of the nasal cavity so that during the vocalisation the animal was vocalising out through its mouth.

像显示喉部在鼻腔中的位置下降，因而在发声过程中动物可以通过口腔发出声。

If they briefly close their mouth and continue vocalising, air will come out of their nose, thus making the m-sound that is used in " mother" around the world.

如果他们短暂地闭上嘴巴并继续发声，空气就会从他们的鼻子里出来， 从而发出世界各地用于“母亲” 的 m 。

The mammalian vocal tract is incredibly flexible so whether we're looking at dogs or pigs or goats or monkeys, we always see the same thing, that the, the anatomy rearranges itself very dynamically while the animal is vocalising.

哺乳动物的声道长度变化相当灵活，不论是观测猪、狗，还是山羊、猴子，我们总能看到同样的结果它们的生理结构随发声过程动态地变化着。