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(Music)
(音樂)
(City traffic) So I'm here today to encourage you to think about New York City,
(城市交通)今天我在這裡 想鼓勵你們想一下紐約這個城市
not just as one of humanity's greatest achievements,
它不僅是人類最大的成就
but as home to native wildlife that are subject to a grand evolutionary experiment.
也是原始野生動物 經歷重大演化實驗的家
So take this forested hillside in northern Manhattan, for example.
就拿這片位於北曼哈頓島 樹木叢生的山坡為例
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.
這是城內最後一片淨土 乾淨的泉水仍從地面湧出
You could drink this out of your hands and you'd be OK.
你能以手接泉水直接飲用,不會生病
These tiny little areas of seeping water contain huge populations of Northern Dusky Salamanders
這一小片泉水區 住著龐大數量的暗棕脊口螈
These guys were common in the city
以前這些小東西在城內很常見
maybe sixty years ago,
大約六十年前還有
but now they're just stuck on this single hillside and a few places in Staten Island.
但現在牠們被困在這片山坡 及史坦頓島上幾個地方
Not only do they suffer the indignity of being
被困在這片山坡上
stuck on this hillside,
牠們不僅尊嚴受辱
but we divided the hillside in two
我們還把這片山坡
on two different occasions
在兩個不同的場合一分為二
with bridges crossing from the Bronx into Manhattan.
蓋橋把布朗克斯與曼哈頓島相連
But they're still there
但牠們還存在那兒
on either side of the bridges where you see the red arrows
在橋的兩端,你們看到的紅箭頭處
about 180th street, 167th street.
約在 180 街,167 街
And my lab has found that if you just take a few segments of DNA
我的實驗室發現,如果你拿幾段
from salamanders in those two locations
取自這兩處的蠑螈的 DNA 來看
you can tell which side of the bridge they came from.
你能分辨牠們從橋的哪一端來
We build this single piece of infrastructure
我們建造的基礎建設
that's changed their evolutionary history.
改變了牠們的演化歷史
We can go study these guys, you know, we just go to the hillside
我們要研究這些傢伙,你知道, 只要跑去這片山坡就好
we know where they are, we can flip over rocks, we can catch them.
我們知道牠們在哪, 我們能翻石頭,我們能抓到牠們
There are a lot of other things in New York City though that are not that
但紐約市還有很多其他的東西
easy to capture, such as this guy, a coyote.
並不那麼容易捕捉 就像這傢伙,郊狼
We caught him on an automatic camera trap somewhere,
我們在某處的自動相機陷阱上拍到牠
in an undisclosed location, not allowed to talk about it yet.
地點不能透露,我們不允許討論這地點
But they're moving into New York City for the first time.
但牠們是第一次遷移進紐約市
They're very flexible, intelligent animals.
牠們是非常靈活、聰明的動物
This is one of this year's cubs checking out one of our cameras.
這是一頭今年出生的幼狼 在看我們的相機
And my colleagues and I are very interested in understanding
我的同事和我很有興趣要搞懂
how they're going to spread through the area,
牠們要如何在這片區域拓展
how they're going to survive here, and maybe even thrive.
牠們要如何在這裡生存,甚至大量繁殖
And they're probably coming to a neighborhood near you if they are not already there.
牠們還可能去你家附近 如果牠們還沒占領那塊地方
So, there are some things that are too fast to be caught by hand.
那麼,有些東西跑太快,手抓不到
We can't pick them up on the cameras,
我們無法用相機捕捉
so we actually set up traps all around the New York City and the parks.
所以我們其實在整個紐約市 及其公園內設了陷阱
This is one of our most common activities.
這是我們最常見的活動
Here's some of my students and collaborators getting the traps out and ready.
這是我一些學生及合作者 把陷阱拿出去架好
And this guy, we catch in almost every forested area in New York City.
而這個傢伙,在紐約市 有樹林的地方幾乎都能抓到
This is the White-footed Mouse.
這是隻白足鼠
This is not the mouse you find running around your apartment.
這不是那種你偶爾看到 在你的公寓裡跑來跑去的老鼠
This is a native species, been here long before humans,
這是一種原生種 在人類出現前就已在這裡生存
and you find them in forests and meadows.
你能在樹林及草原上看到牠們
Because they're so common in forested areas in the city,
因為牠們在都市中 有樹林的地方如此常見
we're using them as a model to understand how species are adapting to urban environments.
我們現在以牠們為模範 來瞭解物種如何適應都市環境
So if you think back 400 years ago,
那麼,如果你回想 400 年前
the five boroughs would have been covered
這五個城區都還被
in forests and other types of vegetation.
森林及其他植物覆蓋
This mouse would have been everywhere.
這種老鼠其實隨處可見
Huge populations that showed few genetic differences across the landscape.
整片土地龐大的老鼠族群基因差異很小
But if you look at the situation today,
但如果你看看今天的情況
they're just stuck in these little islands
牠們就只能待在這幾個
of forest scattered around the city.
城內少數有樹林覆蓋的小塊地區
Just using 18 short segments of DNA, we can pretty much take a mouse
僅僅只用 18 小段 DNA 我們就能拿一隻老鼠
somebody could give us a mouse, not tell us where it was from,
某人給我們一隻老鼠 不讓我們知道是從哪來的
and we could determine what park it came from. That's how different they've become.
然後我們就能判斷牠是從哪個公園來的 那就是牠們之間演化的差異
You'll notice in the middle of this colored figured here
你會注意到在這段有顏色的條紋中間
there's some mixed up colors.
有一些混雜的顏色
There are a few parks in the city that are still connected to each other
這個城市內有幾個公園仍然連接在一起
with strips of forest so the mice can run back and forth
以帶狀森林方式相連 所以老鼠可以跑來跑去
and spread their genes so they don't become different,
並散佈牠們的基因 所以牠們沒有差異
but throughout the city, they're mostly becoming different in the parks.
但以整座城市來看 牠們在公園間已變得相當不同
All right, so I'm telling you they're different,
好,所以我說了牠們不一樣
but what does that really mean? What's changing about their biology?
但這代表什麼意義? 牠們在生物學上有什麼變化?
To answer this question
要回答這個問題
we're sequencing thousands of genes from our city mice
我們為我們城市老鼠 定序了數千個基因
and comparing those to thousands of genes from the country mice.
並與鄉下老鼠的數千個基因比較
So their ancestors outside of New York City
牠們的祖先在紐約市外圍
in these big, more wilderness areas.
住在這些較大較原始的區域
Now genes are short segments of DNA
那麼,基因是小片段的DNA
that code for amino acids.
是組成胺基酸的密碼
And amino acids are the building blocks of proteins.
而胺基酸是蛋白質組成的元件
Now if a single base pair changes in a gene, you can get a different amino acid,
那如果某個基因裡有一對鹼基配對變了
which will then change the shape and structure of the protein.
你就會得到不同的胺基酸
If you change the structure of a protein,
這樣就會跟著改變蛋白質的形狀及結構
you often change something about what it does in the organism.
如果你改變了某種蛋白質的結構
Now if that change leads to a longer life or more babies for a mouse,
你通常就會改變它在生物體裡的功能
something evolutionary biologists call fitness,
那麼如果這種改變會使老鼠的 壽命更長或生更多寶寶
then that single base pair change will spread quickly in an urban population.
跟演化有關,生物學家就稱之為適存度
So this crazy figure is actually called a Manhattan plot,
那麼那對配對的改變 就會在城市的族群中快速散播
because it kind of looks like a skyline.
所以這張怪怪的圖 其實是叫曼哈頓散佈圖
And each dot represents one gene,
因為它看起來有點像建築物的輪廓
and the higher the dot is in the plot,
那每個點都代表一個基因
the more different it is between city and country mice.
在這圖上的點愈高
The ones kind of at the tips of the skyscrapers are the most different,
其在城市與鄉村老鼠間的差異就愈大
especially those above the red line.
這些約在輪廓頂端的是差異最大的
And these genes encode for things like immune response to disease,
尤其是在紅線之上的那些
because there might be more disease
這些基因是免疫系統 如何對抗疾病等的編碼
in very dense, urban populations.
因為可能有更多的疾病出現
Metabolism, how the mice use energy,
在密度高的都市族群裡
and heavy metal tolerance. You guys can probably predict that
代謝作用,老鼠如何使用能量
New York City soils are pretty contaminated with
及重金屬耐受性。你們大概可以預測到
lead, and chromium and that sort of thing.
紐約市的土壤頗受
And now our hard work is really starting,
鉛、鉻這類東西汙染
we're going back into the wilds of New York City parks,
那現在我們辛苦的工作要真正開始了
following the lives of individual mice and seeing exactly what these genes are doing for them.
我們要回到紐約市公園的荒地
And I would encourage you guys to try to look at your parks in a new way,
追蹤個別老鼠的生活 及看這些基因究竟如何在他們身上運作
I'm not going to be the next Charles Darwin,
而我鼓勵大家試著 以新的方式看你家附近的公園
but one of you guys might be, so just keep your eyes open. Thank you.
我不會變成第二個查爾斯·達爾文
(Applause)
但在座之一可能會 所以千萬要睜大你的眼睛,謝謝
(Music)
(掌聲)