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

大城市里的进化论 – 译学馆
未登陆,请登陆后再发表信息
最新评论 (0)
播放视频

大城市里的进化论

Evolution in a Big City

(音乐)
(Music)
(城市交通)今天我在这裡 想鼓励你们想一下纽约这个城市
(City traffic) So I’m here today to encourage you to think about New York City,
它不仅是人类最大的成就
not just as one of humanity’s greatest achievements,
也是原始野生动物 经歷重大演化实验的家
but as home to native wildlife that are subject to a grand evolutionary experiment.
就拿这片位於北曼哈顿岛 树木丛生的山坡為例
So take this forested hillside in northern Manhattan, for example.
这是城内最后一片净土 乾净的泉水仍从地面涌出
This is one of the last areas left in the city where there is clean spring water that’s still seeping out of the ground.
你能以手接泉水直接饮用,不会生病
You could drink this out of your hands and you’d be OK.
这一小片泉水区 住著庞大数量的暗棕脊口螈
These tiny little areas of seeping water contain huge populations of Northern Dusky Salamanders
以前这些小东西在城内很常见
These guys were common in the city
大约六十年前还有
maybe sixty years ago,
但现在牠们被困在这片山坡 及史坦顿岛上几个地方
but now they’re just stuck on this single hillside and a few places in Staten Island.
被困在这片山坡上
Not only do they suffer the indignity of being
牠们不仅尊严受辱
stuck on this hillside,
我们还把这片山坡
but we divided the hillside in two
在两个不同的场合一分為二
on two different occasions
盖桥把布朗克斯与曼哈顿岛相连
with bridges crossing from the Bronx into Manhattan.
但牠们还存在那儿
But they’re still there
在桥的两端,你们看到的红箭头处
on either side of the bridges where you see the red arrows
约在 180 街,167 街
about 180th street, 167th street.
我的实验室发现,如果你拿几段
And my lab has found that if you just take a few segments of DNA
取自这两处的蠑螈的 DNA 来看
from salamanders in those two locations
你能分辨牠们从桥的哪一端来
you can tell which side of the bridge they came from.
我们建造的基础建设
We build this single piece of infrastructure
改变了牠们的演化歷史
that’s changed their evolutionary history.
我们要研究这些傢伙,你知道 只要跑去这片山坡就好
We can go study these guys, you know, we just go to the hillside
我们知道牠们在哪 我们能翻石头,我们能抓到牠们
we know where they are, we can flip over rocks, we can catch them.
但纽约市还有很多其他的东西
There are a lot of other things in New York City though that are not that
并不那麼容易捕捉 就像这傢伙,郊狼
easy to capture, such as this guy, a coyote.
我们在某处的自动相机陷阱上拍到牠
We caught him on an automatic camera trap somewhere,
地点不能透露,我们不允许讨论这地点
in an undisclosed location, not allowed to talk about it yet.
但牠们是第一次迁移进纽约市
But they’re moving into New York City for the first time.
牠们是非常灵活、聪明的动物
They’re very flexible, intelligent animals.
这是一头今年出生的幼狼 在看我们的相机
This is one of this year’s cubs checking out one of our cameras.
我的同事和我很想要搞懂
And my colleagues and I are very interested in understanding
牠们要如何在这片区域拓展
how they’re going to spread through the area,
牠们要如何在这裡生存,甚至大量繁殖
how they’re going to survive here, and maybe even thrive.
牠们还可能去你家附近 如果牠们还没占领那块地方
And they’re probably coming to a neighborhood near you if they are not already there.
那麼,有些东西跑太快,手抓不到
So, there are some things that are too fast to be caught by hand.
我们无法用相机捕捉
We can’t pick them up on the cameras,
所以我们其实在整个纽约市 及其公园内设了陷阱
so we actually set up traps all around the New York City and the parks.
这是我们最常见的活动
This is one of our most common activities.
这是我一些学生及合作者 把陷阱拿出去架好
Here’s some of my students and collaborators getting the traps out and ready.
而这个傢伙,在纽约市 有树林的地方几乎都能抓到
And this guy, we catch in almost every forested area in New York City.
这是隻白足鼠
This is the White-footed Mouse.
这不是那种你偶尔看到 在你的公寓裡跑来跑去的老鼠
This is not the mouse you find running around your apartment.
这是一种原生种 在人类出现前就已在这裡生存
This is a native species, been here long before humans,
你能在树林及草原上看到牠们
and you find them in forests and meadows.
因為牠们在都市中 有树林的地方如此常见
Because they’re so common in forested areas in the city,
我们现在以牠们為模范 来瞭解物种如何适应都市环境
we’re using them as a model to understand how species are adapting to urban environments.
那麼,如果你回想 400 年前
So if you think back 400 years ago,
这五个城区都还被
the five boroughs would have been covered
森林及其他植物覆盖
in forests and other types of vegetation.
这种老鼠其实随处可见
This mouse would have been everywhere.
整片土地庞大的老鼠族群基因差异很小
Huge populations that showed few genetic differences across the landscape.
但如果你看看今天的情况
But if you look at the situation today,
牠们就只能待在这几个
they’re just stuck in these little islands
城内少数有树林覆盖的小块地区
of forest scattered around the city.
仅仅只用 18 小段 DNA 我们就能拿一隻老鼠
Just using 18 short segments of DNA, we can pretty much take a mouse
某人给我们一隻老鼠 不让我们知道是从哪来的
somebody could give us a mouse, not tell us where it was from,
然后我们就能判断牠是从哪个公园来的 那就是牠们之间演化的差异
and we could determine what park it came from. That’s how different they’ve become.
你会注意到在这段有顏色的条纹中间
You’ll notice in the middle of this colored figured here
有一些混杂的顏色
there’s some mixed up colors.
这个城市内有几个公园仍然连接在一起
There are a few parks in the city that are still connected to each other
以带状森林方式相连 所以老鼠可以跑来跑去
with strips of forest so the mice can run back and forth
并散佈牠们的基因 所以牠们没有差异
and spread their genes so they don’t become different,
但以整座城市来看 牠们在公园间已变得相当不同
but throughout the city, they’re mostly becoming different in the parks.
好,所以我说了牠们不一样
All right, so I’m telling you they’re different,
但这代表什麼意义? 牠们在生物学上有什麼变化?
but what does that really mean? What’s changing about their biology?
要回答这个问题
To answer this question
我们為我们城市老鼠 定序了数千个基因
we’re sequencing thousands of genes from our city mice
并与乡下老鼠的数千个基因比较
and comparing those to thousands of genes from the country mice.
牠们的祖先在纽约市外围
So their ancestors outside of New York City
住在这些较大较原始的区域
in these big, more wilderness areas.
那麼,基因是小片段的DNA
Now genes are short segments of DNA
是组成胺基酸的密码
that code for amino acids.
而胺基酸是蛋白质组成的元件
And amino acids are the building blocks of proteins.
那如果某个基因裡有一对硷基配对变了
Now if a single base pair changes in a gene, you can get a different amino acid,
你就会得到不同的胺基酸
which will then change the shape and structure of the protein.
这样就会跟著改变蛋白质的形状及结构
If you change the structure of a protein,
如果你改变了某种蛋白质的结构 你通常就会改变它在生物体裡的功能
you often change something about what it does in the organism.
那麼如果这种改变会使老鼠的 寿命更长或生更多宝宝
Now if that change leads to a longer life or more babies for a mouse,
跟演化有关,生物学家就称之為适存度
something evolutionary biologists call fitness,
那麼那对配对的改变 就会在城市的族群中快速散播
then that single base pair change will spread quickly in an urban population.
所以这张怪怪的图 其实是叫曼哈顿散佈图
So this crazy figure is actually called a Manhattan plot,
因為它看起来有点像建筑物的轮廓
because it kind of looks like a skyline.
那每个点都代表一个基因
And each dot represents one gene,
在这图上的点愈高
and the higher the dot is in the plot,
其在城市与乡村老鼠间的差异就愈大
the more different it is between city and country mice.
这些约在轮廓顶端的是差异最大的
The ones kind of at the tips of the skyscrapers are the most different,
尤其是在红线之上的那些
especially those above the red line.
这些基因是免疫系统 如何对抗疾病等的编码
And these genes encode for things like immune response to disease,
因為可能有更多的疾病出现
because there might be more disease
在密度高的都市族群裡
in very dense, urban populations.
代谢作用,老鼠如何使用能量
Metabolism, how the mice use energy,
及重金属耐受性。你们大概可以预测到
and heavy metal tolerance. You guys can probably predict that
纽约市的土壤颇受
New York City soils are pretty contaminated with
铅、铬这类东西污染
lead, and chromium and that sort of thing.
那现在我们辛苦的工作要真正开始了
And now our hard work is really starting,
追踪个别老鼠的生活
we’re going back into the wilds of New York City parks,
及看这些基因究竟如何在牠们身上运作
following the lives of individual mice and seeing exactly what these genes are doing for them.
而我鼓励大家试著 以新的方式看你家附近的公园
And I would encourage you guys to try to look at your parks in a new way,
我不会变成第二个查尔斯·达尔文
I’m not going to be the next Charles Darwin,
但在座之一可能会 所以千万要睁大你的眼睛,谢谢
but one of you guys might be, so just keep your eyes open. Thank you.
(掌声)
(Applause)
(音乐)
(Music)

发表评论

译制信息
视频概述
听录译者

收集自网络

翻译译者

收集自网络

审核员

自动通过审核

视频来源

https://www.youtube.com/watch?v=ckGB5lHyzME

相关推荐