评论
打印
I have a cat. Her name is Cameo, she's adorable, and recently she peed inside of a potted plant.
我有一只叫Cameo的喵，她非常可爱，最近她总去盆栽里嘘嘘。
But can you imagine how amazing it would be if she could roar… while peeing inside of a potted plant?
但是你能想象她一边在盆栽里嘘嘘一边嘶吼的场景么？
She'd be like, "give me some treats" and then like ferocious roar... it would be so cute!
就像是说，“我要小鱼干”，然后开始嘶吼...那一定会非常可爱吧！
But domestic cats can't roar. Only four species in the cat family can: lions, tigers, leopards, and jaguars.
但是家猫可不会嘶吼。只有四种猫科动物可以：狮子、老虎、豹子和美洲虎。
Here's the weird thing, though: zoologists are pretty sure those four species of cats can't purr.
不可思议的是，动物学家非常确信，这四种猫科动物不会发出呜呜声。
So even though my cat can't roar, the reason probably has a lot to do with the things in her throat that let her purr.
所以尽管我的喵不会嘶吼，但是她可以发出呜呜声，这一定与她喉咙里的某些东西有关。
Now, we still aren't - this is amazing - totally sure how cats purr.
如今，我们依然无法确信猫是如何发出呜呜声的。
There's no, like, "purr box" that we can locate in a cat,
并没有“呜呜箱”这种东西能够用于定位一只猫，
and no one's ever stuck a purring cat in an MRI to find out exactly what's happening.
也从来没有人能够在MRI中困住一只猫，乖乖的让我们检查其中奥秘。
But we've known for a while that it probably involves the larynx, aka the voice box.
但是我们一直都知道，这可能与喉（也称喉头）有关。
Back in 1834, a British zoologist named Richard Owen noticed that
1834年，一位名叫理查德·欧文的英国动物学家发现
there was an anatomical difference between the cat species that purred and the ones that roared
会呜呜的猫和会嘶吼的猫有结构上的差异：
roaring cats had a more flexible hyoid.
嘶吼猫类有着更加灵活的舌骨。
The hyoid is a structure that supports the tongue and larynx. In humans, it's horseshoe-shaped.
舌骨是支撑舌头和和喉头的一个构造。人类的舌骨是马蹄状的。
It's basically the first bone under your chin in the front of your neck,
舌骨基本上是位于你脖子上边，下巴底下的第一块骨头，
although, you shouldn't be able to feel it from the outside, so maybe don't go squeezing up around in there.
虽然，你可能从外边摸不到它，但是也不要挤压它。
On the murder shows, it's how they know people called strangled when they got killed.
在仿谋杀秀上，他们正是通过这一点来判断死者是被勒死的。
They're always like, "the hyoid is broken! That's how we know that the murder was the squeezy neck kind."
他们通常都会说，“死者舌骨破裂！是被勒死的，这是谋杀案。”
In cats, the hyoid is more of a hook that hangs down and connects the back of the skull to the front of the larynx and the base of the tongue.
对于猫科动物来说，舌骨是钩挂和连接背骨与前部喉头的吊钩，位于舌根部。
In most species of cat, including the domestic cat, the hyoid bone is very … bony.
大多数猫科动物包括家猫，它们的舌骨非常...瘦窄。
It's said to be completely ossified, meaning that it's fully hardened bone.
据说也非常僵硬，这就意味着它们的舌骨是完全坚硬的骨头。
And all of the cats that have a completely ossified hyoid can purr, but don't roar.
所有拥有僵硬舌骨的猫都能发出呜呜声，而无法嘶吼。
The cats that do roar don't have a fully ossified hyoid, meaning that it hasn't fully hardened into bone, so it's a lot more flexible.
会嘶吼的猫都没有僵硬的舌骨，这意味着它们的舌骨还没有完全硬化成骨头，因此更加灵活。
The tissue is more like the ligaments that normally connect bones to each other.
组织就像是韧带，通常连接着每块骨头。
Owen thought that flexibility was the key to roaring.
欧文认为灵活性是嘶吼的关键。
Roaring is a low, deep, resonant sound, so cats need long vocal folds to do it, just like people with longer vocal folds have deeper voices.
嘶吼是一种低沉而洪亮的声音，因此猫科动物需要很长的声襞才能嘶吼，就像有着更长声襞的人类，他们的声音更加低沉。
And Owen figured a more flexible hyoid was what let a cat's vocal folds stretch enough for them to roar.
欧文发现更加灵活的舌骨使得猫科动物能充满伸展它们的声襞并发出嘶吼声。
For a long time, pretty much everyone agreed with this idea.
一直以来，相当多的人都同意这个观点。
They also assumed that hardened, bony hyoids were the reason why all the species of cat that couldn't roar could purr.
他们也假定坚硬和瘦窄是解释所有种类的猫能发出呜呜声而无法嘶吼的原因。
But there is one exception: the snow leopard.
但是也有例外：雪豹。
Snow leopards don't have a fully hardened hyoid — they have the more flexible kind that lions do. But they can't roar.
雪豹的舌骨并非完全坚硬——它们和狮子一样拥有灵活的舌骨。但是它们却不会嘶吼。
And even though we've known about the snow leopard exception since at least 1916, scientists didn't really question the hyoid idea until the late 1980s.
尽管我们至少在1916年就知道雪豹这个例外，但是直至1980年代末，科学家也没有真正质疑过舌骨概念。
That was when researchers realized that there is another difference between cats that can roar and cats that can't:
从那时开始，研究者才意识到会呜呜和会嘶吼的猫科动物之中还存在其他差异：
roaring cats have thick pads of tissue on their vocal folds.
嘶吼猫科动物的声襞中的衬垫组织较厚。
The pads make their vocal folds longer and heavier, which allows them to vibrate more slowly and make a lower-pitched sound.
衬垫使得它们的声襞更长、更重，让它们可以缓慢的颤动并发出更加低频的声音。
Only lions, tigers, leopards, and jaguars have these pads, with no exceptions — not even snow leopards. So roaring isn't entirely about the hyoid bone.
只有狮子、老虎、豹子和美洲虎才拥有这种衬垫，无一例外——就连雪豹也是。所以，嘶吼并不仅仅与舌骨相关。
Sure, the extra flexibility might help, but they also need that extra tissue that our domestic cat friends don't have.
当然，额外的灵活性或许也有帮助，但是它们也需要额外的组织，而这些是家猫所没有的。
These pads also help explain why cats that roar can't purr. When cats purr, they vibrate their vocal folds about 26 times per second.
这种衬垫也能够解释会嘶吼的猫科为何不会呜呜。但猫呜呜时，它们的声襞每秒颤动26次。
There seems to be some mechanism in their brains that controls the vibrations.
似乎在它们的大脑中存在一些机理以控制颤动。
As they inhale and exhale, the vocal folds open and close, which is what makes the purring sound.
当它们吸气呼气时，声襞的张合使它们发出呜呜声。
It's like how you can make that motorboat sound by vibrating your lips, except they do it inside of them with their vocal folds.
就像是，你可以通过唇部发出类似摩托艇的声音，而它们是用它们的声襞在内部发声。
But the extra padding that allows lions, tigers, leopards, and jaguars to roar would dampen the constant vibrations that they'd need to purr.
但是额外的衬垫能够让老虎、狮子、豹子和美洲虎嘶吼，却抑制了声襞的连续颤动使它们无法发出呜呜声。
The females of those species do make purring-like noises when they're in heat,
这些种类的雌性确实可以发出呜呜声——像是遭受炎热时发出的声音，
but those noises don't seem to be quite the same as true purring. They're closer to a growl.
但是这些声音和真正的呜呜声还不太一样。它们更像是咆哮。
So, my cat can't roar because her vocal folds just aren't shaped for it.
所以，我的喵无法嘶吼，因为她的声襞不允许。
But she can purr, and that's pretty dang cute and I like it.
但是她会呜呜，真是太TM可爱啦，我喜欢。
Thanks for watching this episode of SciShow, and thanks to Patreon patron Janet Neidlinger for asking about how cats purr!
谢谢观看这一期的科学秀，谢谢Patreon 赞助人 Janet Neidlinger关于猫如何发出呜呜声的提问！
If you're curious about why cats purr in the first place, check out our video where I explain that it's not necessarily because they're happy.
对为什么猫会呜呜好奇？请点击我们的视频，我们能够为您解答——没必要解释太多，因为她们开心。
