ADM-201 dump PMP dumps pdf SSCP exam materials CBAP exam sample questions

克隆技术能拯救濒危动物吗? – 译学馆
未登录,请登录后再发表信息
最新评论 (0)
播放视频

克隆技术能拯救濒危动物吗?

Why Can’t We Clone Endangered Species to Save Them?

首先非常感谢Skillshare对这期科学秀的支持
Thanks to Skillshare for supporting this episodeof SciShow.
[前奏]
[♪ INTRO]
老虎 大猩猩 犀牛 看来现在已有许多动物濒临灭绝
Tigers, gorillas, rhinos, it seems like there are a lot of animals on the endangered species list these days.
但现在 我们知道如何克隆动物
But we know how to clone animals.
所以 如果问题是犀牛太少的话
So if the problem is too few rhinos,
而我们又刚好知道如何克隆犀牛
and if we know how to make more rhinos
那么问题不就解决了吗 对吧?
problem solved, right?
好吧 确实有人正致力于克隆濒危动物
Well,there actually are people working on cloning endangered animals.
然而事情并不是我们想的那么简单
But it is not as easy as you might think,
而且造成这些物种濒临灭绝的问题
and in the end it still won’t fix the problem
也不会因此而解决
that made those species endangered in the first place.
第一只由成年体细胞克隆的哺乳动物是1996年的多利羊
The first mammal cloned from adult cells was Dolly the sheep back in 1996,
自此科学家们又克隆出了许多别的动物
and since then scientists have cloned a lot of different things,
比如猫 狗 甚至猴子
like cats, dogs, and even monkeys.
不久后 濒危动物也上了克隆名单
And it didn’t take long for endangered animals to get on that list.
例如 21世纪初 研究人员成功克隆了印度野牛
In the early 2000s, for example, researchers cloned a type of wild cow called the gaur.
而后他们继续克隆了其它濒危的牛和野羊
And they went on to clone other endangered cattle, wild sheep
甚至一头已经灭绝的野山羊
and even an extinct wild goat.
虽然这种科学成果很牛
But as cool as these achievements were,
但是这些物种的数量并未因此而增加
none of them ended up really increasing the species’numbers.
这是因为 尽管电影那样演
That’s because, despite what movies might suggest,
现实中我们不可能定制一支克隆军
you can’t just order up an army of clones.
要克隆某样生物 你需要的不仅仅是该物种的原始DNA
To clone something, you typically need more than just some DNA from the original creature.
你还需要能存放DNA的卵细胞来构造一个胚胎
You also need an egg cell to put that DNA into to create an embryo.
然后胚胎还需要植入代孕母体内生长
Then that embryo needs to be implanted in a surrogate mother to develop.
而这些你不能用培养皿代替
You can’t just do this in a petri dish.
也许这些听起来都很简单直观
While that all might sound straightforward enough,
但是取得卵细胞本来就很难 而且对动物来说也存在风险
getting those eggs in the first place can be difficult and risky for the animal.
要知道如何获取卵细胞
To know how to get eggs,
你得非常了解该动物的生殖规律
you need to know a lot about that specific animal’s reproductive biology,
如它们何时排卵 何时生长和释放卵细胞
like when they ovulate, or grow andrelease egg cells.
人类排卵期一般都是有规律的周期
Humans generally ovulate in regular frequent cycles,
但并不是所有的物种都是如此
but not all animals do.
像熊猫就一年排一次卵
Pandas only ovulate once a year, for example,
而像猫之类的动物只在交配之后才排卵
and there are animals like cats that only ovulate after mating.
有时我们可以注射激素来促进排卵
We can sometimes use hormone injections to kick start ovulation,
但每只动物可能需要不同剂量或不同的激素混合
but each animal may need different doses or a different mix of hormones.
之后你仍然需要取卵
And then you still have to get the eggs.
以犀牛为例
Take rhinos, for example.
比如 要从一头1700千克的排卵期犀牛收集卵细胞
Like you try convincing a 1,700 kilogram ovulating rhino to let you collect eggs,
你就需要把一个1.5米长的定制装置放入它的体内
from inside her using a custom-designed,one-and-a-half-meter-long device.
我不敢 我的意思是你可以为它打镇静剂
I won’t,I mean sure you can sedate her.
这也是许多研究者需要做的
Which is definitely what the researchers do.
但是给它打镇静剂的过程也有风险
But sedation also carries risks.
总的来说 从动物体内取卵的过程可能包括多次激素注射
All and all, getting eggs from animals may involve multiple hormonal injections
打麻醉剂或是外科手术等
and the use of anestheticsor surgical procedures,
但是动物们不一定能受得住这么折腾
and not every individual animal is healthy enough to undergo all that.
还有就是你需要收集许多的卵细胞
And also, you need to collect a lot of eggs.
但是DNA和卵细胞不一定融合
The DNA-egg cell fusion doesn’t always work right,
所以你可能需要几百个卵细胞才能培养出一个胚胎
so for each viable embryo, you might need hundreds of egg cells.
而且就算这些步骤你都成功了
And even if you go through all of that,
你还需要一个载体来承载胚胎的孕育
you still need surrogates to carry the pregnancy.
就像取卵那样 你需要清楚的了解动物的生殖生物学
Like collecting eggs, that requires knowledge about the animal’s reproductive biology,
以及很多只健康的雌性动物
as well as lots of healthy female animals;
而且数量要比你需要克隆的数量多
more than just the number of clones you want to make.
因为不幸的是 并不是每个胚胎都能成长为健康的后代
Because unfortunately, not every implantation takes and develops into a healthy offspring.
对数量充裕的物种 或者我们熟悉的物种来说
For plentiful species, or ones we know really well,
比如牛或是羊 这些都不是大问题
like cows or sheep, those might not be big problems.
但是濒临物种的话像老虎或是犀牛
But for endangered species, like tigers or rhinos,
也许没有足够多的雌性动物来配合
there may not be enough female animals to work with.
好消息是现在有新的方法来替代
The good news is that there are ways to kind of cheat.
你可以用较常见的近亲物种的卵或是母体
You can sometimes use eggs or mothers from more common closely related species, for example.
克隆印度野牛宝宝的代孕母体就是一头叫Bessie的普通牛
the baby gaur’s surrogate mom was actually a regular cow named Bessie.
因为 显然其实所有的牛都可以叫Bessie
Because of course, all cows are named Bessie, apparently.
但是混血胚胎在成长的过程中也会有许多其他问题
But hybrid embryos can haveextra problems during development.
科学家目前正在研究新的替代方法
Scientists are working on an alternative to all this:
即用基因重组冷冻组织样本方法来制造卵子和精子
A way to make eggs and sperm by genetically reprogramming frozen tissue samples.
所以有朝一日 我们或许可以只从几只雌性动物身上取卵
So one day we might be able to make a lot of eggs without needing a lot of female animals.
但目前还在初级阶段 而且该方法还需要因动物而异
But that’s still in the very early stages and the process will likely need to be customized for each animal.
我们以后有可能研究出应对这些挑战的方法
Now it’s possible that we might figure out how to solve all of these challenges.
然而 就算我们可以克隆任何我们想要克隆的动物
But even if we could clone any animal we wanted,
这也可能不是我们想找的解决方法
it might not be the fix we were looking for.
一方面 虽然克隆技术可以增加动物的数量
For one thing, even though cloning might increase the number of animals
动物的遗传多样性也可能会因此丢失
You could still end up with a loss of genetic diversity
因为它们基因都是一样的
because they’d all be genetically identical.
这是一件坏事 因为这个过程类似于近亲交配
That’s bad because the population couldeffectively become inbred,
导致后代容易得病或是直接遗传疾病
which can leave them vulnerable to diseases or genetic disorders.
如果你有许多不同个体的冷冻样本的话
If you have frozen tissues from a lot of different individuals,
你不仅可以避免这个问题
you might be able to avoid this issue
甚至还能重新引入已失去的遗传变异
or even reintroduce genetic variation that’s been lost,
但这些还是取决于你的库存
but that will depend on what you’ve stockpiled.
克隆濒危动物的主要问题在于
The real problem with cloning endangered animals
我们不能避免导致物种濒临灭绝的各种因素
is that it won’t stop the poachers, habitat loss, or myriad other things
比如偷猎者行为 动物栖息地的丧失
driving these species extinct in the first place.
克隆花费高昂
Cloning is very expensive,
而且研究者指出 更划算 更有效的方法
and some researchers have pointed out it’s probably cheaper and more effective
就是把钱花在打击偷猎 开发新的自然保护区
to spend that money on fighting poaching, creating new nature reserves,
或是其它传统的保护措施上
or other, more traditional conservation efforts.
尽管如此 研究克隆技术的科学家还是希望
Still scientists working on cloning remain optimistic
该技术有一天能够成为保护动物的有利工具
that could one day become really useful tool for conservation,
比如重新引入遗失的基因
like to reintroduce lost genes
或是为数量稀少的物种筑起最后一道生命防线
or last lifeline to save species whose numbers have dwindled to just a handful.
但是目前我们还是得按老方法来进行老虎和犀牛的克隆
But for now, we’ll have to make all of our tigers and rhions the old fashioned way
在现实世界中克隆动物是一件非常麻烦的事情
Cloning animals in the real world super tricky,
但是临摹画中的动物却是每个人都能做好的
but cloning pictures of animals is something any one can learn to do well
特别是在Skillshare上的PS教程的指导下
especially with the little help from one of the amazing Photoshop classes offered by Skillshare.
但是如果你真的很想提高你的PS技能
But if you really want to up your Photoshop-art game,
你可以看看生活记者Helen Bradley的Skillshare课程
you might want to check out this Skillshare course by lifestyle journalist Helen Bradley
主题是如何做出超现实主义拼贴效果
on how to make surrealist collage effects.
在该课程里 Helen分享了如何使用不同的PS工具
In it, Helen explains how you can use different Photoshop tools
将图片分开然后形成独特的艺术
to split apart an image and make really wacky art,
类似于Julia Geiser在该期视频里的插画
sort of like the prints by the artist featured in the episode, Julia Geiser.
我喜欢这个课程 因为如标题所言
What I love about this class is that, as the title suggests,
Helen把每一点都讲的很清楚很简洁
Helen goes through everything clearly and quickly,
你完全可以在午休期间来学习
so you really can take the class over your lunch break,
同时 Helen在Skillshare上还有别的速学课程
And Helen has a bunch of otherquick courses on Skillshare,
所以你可以试画一些独具风格的涂鸦或是毛茸茸的小动物
so you can try your hand at making stylish doodles or drawing furry creatures.
现在 Skillshare 给科学秀的观众两个月的免费的使用权
Right now, Skillshare is offering SciShow viewers 2 months of unlimited accesses for free
有超过2万节免费课程任你选择
And they have more than 20,000 classes to choose from,
所以不管你想培养哪种业余爱好
so no matter what hobby you want to pursue,
Skillshare上可能就有相关的课程哟
there’s probably a Skillshare course for you to take.
而且你在学习的同时也会支持科学秀
And you’ll be supporting SciShow while you do it.
你可以点击简介中的链接查看哈!
You can follow the link in the description to check it out!
[结束]
[♪ OUTRO]

发表评论

译制信息
视频概述

为什么不能用克隆技术拯救濒临灭绝的动物?或许未来我们会有更好的方法。

听录译者

收集自网络

翻译译者

寻🍃

审核员

审核员B

视频来源

https://www.youtube.com/watch?v=mvXDPLx8-TI

相关推荐