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为什么宠物狗的耳朵是耷拉的 – 译学馆
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为什么宠物狗的耳朵是耷拉的

Why Dogs Have Floppy Ears: An Animated Tale

Here’s a strange thing
有一件奇怪的事情
wolves and coyotes have these big upright ears.
狼和土狼有着直立的大耳朵
All the better to hear you with.
能更好地听到声音
But my dog Zeke here has floppy ears.
但是我的狗狗Zeke耳朵是耷拉的
Why the difference?
为什么会有这种区别呢?
Doesn’t he need to hear too?
难道他就不需要听声音了吗?
Charles Darwin himself actually thought a lot about this question.
查尔斯·达尔文本人对这个问题也思考了很多
150 years ago, he published a book that said
150年前 他出版的一本书中提到
“Look—it’s not just pet dogs!”
“看 不仅是宠物狗耷拉耳朵!”
Pigs have floppier ears than wild boars.
家猪的耳朵比野猪下垂
Farmed goats have floppier ears than wild goats.
农场山羊的耳朵比野山羊下垂
There are floppy-eared rabbits, cows and sheep.
还有耷拉耳朵的兔子 奶牛和绵羊
And that’s not the only weird thing!
而且 这并不是唯一奇怪的地方
Tame animals tend to have shorter snouts,
驯养动物的鼻子往往较短
and their fur tends to be paler
而且它们的毛色也更浅
or have patches with color missing.
或者有缺失颜色的斑块
All these mysterious traits put together have been called
所有这些神秘的特质合在一起 被称为
“domestication syndrome.”
驯化综合征
So,what’s going on here?
所以 这是怎么回事?
《NPR浣熊》
The story starts thousands and thousands of years ago
故事开始于几千年前
when humans were surrounded by animals.
人类周围还有很多动物的时候
Some animals were scary, and some were a bit more approachable
一些动物很可怕 一些更容易接近
even potentially useful.
甚至可能有用
Our ancestors wanted them to be tamer, so sometimes
我们的祖先想让它们更温顺
they tried breeding the friendliest ones.
所以有时他们会尝试繁育最友好的品种
At some point, strange side effects started to show up
在某个时候 奇怪的副作用开始显现
Thousands of years later,
几千年后
good old Darwin noticed the domestication syndrome pattern,
达尔文注意到了驯化综合征的模式
but all he’d learned about change in the animal kingdom
但是以他对动物世界变化的了解
couldn’t explain this connection between behavior and appearance.
他还是解释不了行为和外表之间的联系
Scientists who came after him couldn’t figure it out either.
在他之后的科学家也没有弄清楚
But for the past few years,
但是过去几年里
scientists have been throwing around a fascinating hypothesis.
科学家们提出了一个很有趣的假说
They think the answer to this whole puzzle lies
他们认为这个谜题的答案在于
in a special group of cells.
一组特殊的细胞
They’re called neural crest cells, and coincidentally,
它们被称为神经嵴细胞 巧合的是
they were discovered by Wilhelm His the exact same year
这些细胞是由威尔赫姆·希斯
Darwin published his book.
在达尔文出版他的书那年发现的
Neural crest cells show up very early in the development of all vertebrate embryos.
神经嵴细胞在所有脊椎动物胚胎发育的早期就出现了
As the embryo grows
随着胚胎发育成
into a goat or a pig or a wolf,
一只山羊 猪或者狼
these special cells travel to every corner of the body
这些特殊的细胞将遍布身体的每一个角落
and take on all sorts of different jobs.
承担各种不同的工作
Now, here’s the thing:
现在 事情是这样的
Some of these cells end up right here above the kidneys.
其中一些细胞会移到肾脏上面
They become cells that secrete adrenaline
它们变成分泌肾上腺素的细胞
—that famous fight-or-flight hormone.
也就是著名的战斗或逃跑激素
Wild animals are always fighting or fleeing to survive,
野生动物总是为了生存而战斗或逃跑
and that makes it hard for humans to get close.
这使得人类很难接近它们
But what if an animal was born
但是 如果一种动物天生
with fewer of these neural crest cells,
具有较少的这种神经嵴细胞
or those cells didn’t work so well?
或者这些细胞的功能不太好怎么办
That animal would have less adrenaline.
这种动物的肾上腺素就会减少
It would probably be less freaked out by humans—
它可能不会被人类吓到
and it would pass that behavior on to its offspring.
而且可能把这种行为传给它的后代
The idea is that this is what’s going on in domesticated animals.
这就是家养动物的情况
Their neural crest cells have been dialed back.
他们的神经嵴细胞的功能被调下来了
And this would explain all the appearance stuff, too
这也可以解释所有的外观问题
because neural crest derived cells do a lot more than just make adrenaline.
因为神经嵴衍生细胞不仅制造肾上腺素
Some of the cells end up forming parts of the face.
一些细胞最终形成了脸的一部分
Some of them become cells that control the color of skin and hair.
其中一些变成了控制皮肤和毛发颜色的细胞
And some make their way into the ears—and help make cartilage.
有些细胞进入耳朵 帮助形成软骨
It’s likely this is how dogs first got floppy ears.
这很可能就是狗狗的耳朵变得耷拉的原因
And then centuries of intentional human breeding
而人类几个世纪以来的有意识的繁殖
helped accentuate or reverse that change.
帮助强调或逆转了这一变化
But the neural crest cell hypothesis doesn’t quite explain every bit of domestication syndrome.
但是神经嵴细胞假说并不能完全解释驯化综合症的形成
Like—what’s going on with other tame species that do have upright ears?
比如 其他有直立耳朵的驯养动物是怎么回事
This be might be the excuse scientists need
这可能成为科学家们需要花更多时间
to spend more time with their pets.
和他们的宠物在一起的借口
This is Skunk Bear—NPR’s science show
这里是浣熊——NPR的科学秀
Please subscribe and check out some papers
请订阅并查看
about the neural crest cell hypothesis down in the description
下面简介中关于神经嵴细胞假说的一些论文

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视频概述

为什么宠物狗的耳朵是耷拉的?除此之外,很多家畜也有着下垂的耳朵,观看本视频来了解其中的奥秘吧~

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收集自网络

翻译译者

阿丁

审核员

审核员B

视频来源

https://www.youtube.com/watch?v=R7flhfV31-0

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