Deborah Gordon: The emergent genius of ant colonies

譯者: Wei Ming Chao 審譯者: Marie Wu

I study ants, and that's because I like to think about how organizations work.

我研究螞蟻，因為我喜歡思考組織的運作方式，

And in particular, how the simple parts of organizations

尤其想知道，單一的個體是如何透過互動的方式，

interact to create the behavior of the whole organization.

就能創造出複雜完整的組織行為。

So, ant colonies are a good example of an organization like that,

而蟻群就是最好的例子，

and there are many others. The web is one.

其它像是網路，

There are many biological systems like that --

很多的生物系統，像是

brains, cells, developing embryos.

大腦、細胞、發育中的胚胎都是類似的例子。

There are about 10,000 species of ants.

螞蟻大約有一萬多種品種，

They all live in colonies consisting of one or a few queens,

他們的蟻群都會有一隻或幾隻蟻后，

and then all the ants you see walking around are sterile female workers.

而那些走來走去的螞蟻，都是沒有生育能力的雌性工蟻，

And all ant colonies have in common that there's no central control.

而且所有蟻群都有一個共同點，就是他們沒有中央領導。

Nobody tells anybody what to do.

沒有任何一隻工蟻被告知該做什麼事，

The queen just lays the eggs. There's no management.

蟻后只顧生蛋，她並不做任何管理的事情，

No ant directs the behavior of any other ant.

沒有任何一隻螞蟻指揮其它螞蟻該做什麼事，

And I try to figure out how that works.

我想試著了解他們是怎麼運作的，

And I've been working for the past 20 years

所以我過去二十年，

on a population of seed-eating ants in southeastern Arizona.

一直在亞利桑那州的東南部，研究一種會吃種子的螞蟻，

Here's my study site. This is really a picture of ants,

這就是我研究的地方。這真的是一張螞蟻的照片，

and the rabbit just happens to be there.

只是剛好有隻兔子在那。

And these ants are called harvester ants because they eat seeds.

這些螞蟻被稱作收割蟻，因為他們吃種子。

This is the nest of the mature colony, and there's the nest entrance.

這是一個發展健全的蟻巢，而且那裡有一個入口，

And they forage maybe for about 20 meters away,

裡面的螞蟻們可能會到20公尺遠的地方覓食，

gather up the seeds and bring them back to the nest, and store them.

蒐集種子並且把它們帶回巢穴儲存。

And every year I go there and make a map of my study site.

每一年我都會去那裡，製作一張蟻群分佈的地圖，

This is just a road. And it's not very big:

只是一條路的範圍，不是很大，

it's about 250 meters on one side, 400 on the other.

大約有250公尺長，400公尺寬。

And every colony has a name, which is a number,

這裡的每個蟻群都有各自的編號，

which is painted on a rock. And I go there every year

編號被標記在石頭上，所以每年我都可以回去那裡，

and look for all the colonies that were alive the year before,

找出所有蟻群過去一年居住的位置，

and figure out which ones have died, and put all the new ones on the map.

然後觀察哪些蟻群已經滅絕，並在地圖上標註出新蟻群。

And by doing this I know how old they all are.

持續透過這樣的工作，我可以知道這些蟻群活了多久，

And because of that, I've been able to study how their behavior changes

也因為如此，隨著蟻群的成長及擴張，

as the colony gets older and larger.

我可以研究他們的行為變化。

So I want to tell you about the life cycle of a colony.

我想先來談談關於蟻群的生命週期。

Ants never make more ants; colonies make more colonies.

絕大部分的螞蟻不能繁殖，但蟻群卻可以生產更多蟻群，

And they do that by each year sending out the reproductives --

這是因為他們每年都會派出那些有翅膀的生殖蟻，

those are the ones with wings -- on a mating flight.

飛到蟻穴之外交配。

So every year, on the same day -- and it's a mystery exactly how that happens --

而且很神奇的，都剛好在每年的同一天，

each colony sends out its virgin, unmated queens with wings, and the males,

每個蟻群都會在那天送出長有翅膀的新蟻后與公蟻，

and they all fly to a common place. And they mate.

一起飛到同個地方交配。

And this shows a recently virgin queen. Here's her wings.

這是一隻最近拍攝到的新蟻后，那是她的翅膀，

And she's in the process of mating with this male,

她正在跟這隻公蟻交配，

and there's another male on top waiting his turn.

而且還有另一隻公蟻在上面等，等待輪到他交配。

Often the queens mate more than once.

通常每隻新蟻后都會交配一次以上，

And after that, the males all die. That's it for them.

交配完，公蟻就會死，那就是他們的用處。

(Laughter)

(笑聲)

And then the newly mated queens fly off somewhere, drop their wings,

接著這些懷孕的新蟻后會飛到某個地方，褪去她們的翅膀，

dig a hole and go into that hole and start laying eggs.

挖一個洞，鑽進去，然後開始產卵。

And they will live for 15 or 20 years, continuing to lay eggs

她們會活15到20年，並且利用與公蟻交配時留下的精液，

using the sperm from that original mating.

每年持續不斷地產卵。

So the queen goes down in there.

女王由此誕生。

She lays eggs, she feeds the larvae -- so an ant starts as an egg, then it's a larva.

螞蟻是卵生的，女王會持續地產卵並扶養幼蟲，

She feeds the larvae by regurgitating from her fat reserves.

她利用反芻的方式，將體內豐富的貯存物餵食給幼蟲，

Then, as soon as the ants -- the first group of ants -- emerge,

然後，她的第一批子民開始湧現，

they're larvae. Then they're pupae. Then they come out as adult ants.

他們很快地從幼蟲變成蛹，然後破繭而出變為成蟻。

They go out, they get the food, they dig the nest,

這些成蟻會出去找食物，或蓋巢穴，

and the queen never comes out again.

而女王從此不再踏出她的王宮。

So this is a one-year-old colony -- this happens to be 536.

這是一個一歲大的蟻群，它的編號是536，

There's the nest entrance, there's a pencil for scale.

那裡有一個巢穴的入口，鉛筆是比例尺，

So this is the colony founded by a queen the previous summer.

這是由某隻蟻后在去年夏天所建立的。

This is a three-year-old colony.

這是一個三歲大的蟻群，

There's the nest entrance, there's a pencil for scale.

巢穴的入口在那裡，鉛筆是比例尺，

They make a midden, a pile of refuse -- mostly the husks of the seeds that they eat.

他們在那裡丟了一堆廢棄物，大部分是吃剩的穀殼。

This is a five-year-old colony. This is the nest entrance, here's a pencil for scale.

這是一個五歲大的蟻群，那是巢穴入口，鉛筆是比例尺，

This is about as big as they get, about a meter across.

這蟻群已成長至最大，大約一公尺長。

And then this is how colony size and numbers of worker ants changes --

這張圖是用來觀察蟻群大小和工蟻數的變化，

so this is about 10,000 worker ants --

所以這(五歲大的)蟻群大約有一萬隻工蟻，

changes as a function of colony age, in years.

蟻群大小的變化是蟻群年紀的函數，單位是年。

So it starts out with zero ants, just the founding queen,

所以蟻群在蟻后建立之初，並沒有任何其它的螞蟻，

and it grows to a size of about 10 or 12 thousand ants when the colony is five.

但在五年後，它會成為一萬到一萬兩千隻螞蟻的蟻群，

And it stays that size until the queen dies

並且在蟻后死去之前，一直維持這樣的數量規模，

and there's nobody to make more ants, when she's about 15 or 20 years old.

蟻后約在15到20歲時便停止生產。

And it's when they reach this stable size, in numbers of ants,

而當蟻群的數量達到穩定的大小時，

that they start to reproduce.

它就會開始複製新的蟻群，

That is, to send more winged queens and males to that year's mating flight.

也就是一年一度送出有翅的新蟻后與公蟻，讓他們飛到外面交配。

And I know how colony size changes as a function of colony age

而我之所以敢說蟻群的大小會隨著蟻群年紀變化，

because I've dug up colonies of known age and counted all the ants. (Laughter)

是因為我挖開過每一個已知歲數的蟻群，還數過所有螞蟻的數量，

So that's not the most fun part of this research, although it's interesting.

這還不算是這研究最好玩的部分，不過是蠻很有趣的啦。

(Laughter)

(笑聲)

Really the question that I think about with these ants is what I call task allocation.

其實我真正想從這些螞蟻身上了解的是"任務分配"的問題，

That's not just how is the colony organized,

這不僅僅是蟻群如何組織的問題，

but how does it change what it's doing?

而是蟻群如何改變自己的行為?

How is it that the colony manages to adjust

當狀況有變時，他們如何

the numbers of workers performing each task as conditions change?

調派足夠的工蟻去執行各項工作？

So, things happen to an ant colony.

蟻群可能會碰到下面這些狀況：

When it rains in the summer, it floods in the desert.

夏天的雨水會淹沒這片沙漠，

There's a lot of damage to the nest,

而重創蟻巢，

and extra ants are needed to clean up that mess.

那麼就需要多派些螞蟻來災後重建；

When extra food becomes available --

而當有螞蟻發現新的食物，

and this is what everybody knows about picnics --

每隻螞蟻都會知道野餐時間到了，

then extra ants are allocated to collect the food.

那麼就要多分派些螞蟻去搬回這些食物。

So, with nobody telling anybody what to do, how is it that

所以，在沒有任何人指揮的情況下，

the colony manages to adjust the numbers of workers performing each task?

蟻群是如何做到派遣足夠的工蟻去執行各項任務的呢?

And that's the process that I call task allocation.

而這就是我所謂的"任務分配"問題。

And in harvester ants, I divide the tasks

我將這種收割蟻所做的可能任務，

of the ants I see just outside the nest

依照我在巢穴外觀查到的，

into these four categories: where an ant is foraging,

分成四大類，首先是覓食分隊，

when it's out along the foraging trail, searching for food or bringing food back.

他們的任務就是沿著覓食路徑出去找食物，並從原路帶食物回來。

The patrollers -- that's supposed to be a magnifying glass --

再來是巡邏分隊--他們應該需要放大鏡--

are an interesting group that go out early in the morning

他們是很有趣的分隊，每天一大早

before the foragers are active.

在覓食分隊行動前，他們就出門了。

They somehow choose the direction that the foragers will go,

不知他們是怎麼選擇方向的，

and by coming back -- just by making it back --

不過他們來回的路徑，就是之後覓食分隊的覓食路徑，

they tell the foragers that it's safe to go out.

他們會告訴覓食分隊這些路是安全的。

Then the nest maintenance workers work inside the nest,

再來是在蟻巢內工作的修護分隊，

and I wanted to say that the nests look a lot like Bill Lishman's house.

我想說的是通常蟻巢看起就跟比爾.里斯曼的房子差不多，

That is, that there are chambers inside,

也就是說裡面都是房間，

they line the walls of the chambers with moist soil

他們用潮濕的土壤來造隔間的牆，

and it dries to a kind of an adobe-like surface in it.

牆乾了就會形成像泥磚般的表面。

It also looks very similar to some of the cave dwellings

蟻巢看起來也很像某些

of the Hopi people that are in that area.

當地印地安人的洞穴居。

And the nest maintenance workers do that inside the nest,

此外修護工人們在造牆時，

and then they come out of the nest carrying bits of dry soil in their mandibles.

他們也會用大顎搬一些乾掉的的泥土到巢穴外，

So you see the nest maintenance workers come out with a bit of sand,

所以你可以看到修護工人夾著一些沙出來，

put it down, turn around, and go back in.

放在地上，轉個身，然後又回去洞穴。

And finally, the midden workers put some kind of territorial chemical in the garbage.

最後是堆肥分隊，他們會把當地取得的某種化學物質放在垃圾中，

So what you see the midden workers doing is making a pile of refuse.

你會看到堆肥分隊不斷地在堆放廢棄物。

On one day, it'll all be here, and then the next day

可能今天他們把廢棄物堆在這裡，

they'll move it over there, and then they'll move it back.

隔天把它移到另一個地方，然後哪一天又把它們移回來，

So that's what the midden workers do.

這就是堆肥分隊的工作。

And these four groups are just the ants outside the nest.

這四個分隊都是需要走出巢穴工作的螞蟻，

So that's only about 25 percent of the colony, and they're the oldest ants.

他們只佔了整個蟻群的四分之一，但他們是年紀最大的螞蟻。

So, an ant starts out somewhere near the queen.

每隻螞蟻都是從蟻后的身邊成長離開，

And when we dig up nests we find they're about as deep

在我們挖了一些蟻巢後，才發現它們的深度

as the colony is wide, so about a meter deep for the big old nests.

跟它們的寬度差不多，也就是說一個大的老巢大約有一公尺深，

And then there's another long tunnel and a chamber, where we often find the queen,

裡面有個很長的地道，底部有個房間，我們常常可以在那裡找到蟻后，

after eight hours of hacking away at the rock with pickaxes.

這大約需要用鶴嘴鋤在土石裡挖八個小時。

I don't think that chamber has evolved because of me and my backhoe

我不認為那個房間會因為我的挖土機或我學生的鶴嘴鋤，

and my crew of students with pickaxes,

就會有所遷移；

but instead because when there's flooding,

但是當水災發生時，

occasionally the colony has to go down deep.

蟻穴偶爾會繼續往更深處挖。

So there's this whole network of chambers.

這是整個蟻穴的地下網絡，

The queen's in there somewhere; she just lays eggs.

蟻后就在那裡某處生蛋；

There's the larvae, and they consume most of the food.

那邊是幼蟲，大部分的食物都是用來餵養他們。

And this is true of most ants --

可以說大部分你平常看到

that the ants you see walking around don't do much eating.

在那走來走去的螞蟻，其實是吃很少的，

They bring it back and feed it to the larvae.

他們主要是把食物帶回去供養那些幼蟲。

When the foragers come in with food, they just drop it into the upper chamber,

當覓食分隊帶著食物回來時，他們通常只是把它放到較上層的存放室，

and other ants come up from below, get the food,

然後下層的螞蟻就會上來搬這些食物，

bring it back, husk the seeds, and pile them up.

把它搬回去後，剝去種子的外殼，並堆放好。

There are nest maintenance workers working throughout the nest.

那邊都是蟻巢的維護分隊，他們遍布整個蟻巢。

And curiously, and interestingly, it looks as though at any time

令人好奇且有趣的是，蟻群似乎總是有

about half the ants in the colony are just doing nothing.

大約一半的螞蟻是不做任何事的，

So, despite what it says in the Bible,

所以儘管聖經提到說：

about, you know, "Look to the ant, thou sluggard,"

"懶鬼啊，看看螞蟻是多麼的勤勞"，

in fact, you could think of those ants as reserves.

事實上，你也許會想說他們可能是後備部隊，

That is to say, if something happened -- and I've never seen anything like this happen,

也就是說，如果發生了某事--不過我倒是從沒看過這"某事"發生過，

but I've only been looking for 20 years --

儘管我只觀察它們二十年 --

if something happened, they might all come out if they were needed.

如果發生了某事，或許他們會傾巢而出也不一定。

But in fact, mostly they're just hanging around in there.

但事實上，大部分的時候他們仍是逗留在蟻巢裡，

And I think it's a very interesting question --

我覺得這是一個非常有趣的問題 --

what is there about the way the colony is organized

蟻群為什麼會是那樣的組織方式？

that might give some function to a reserve of ants who are doing nothing?

那些做為後備部隊不做任何事的螞蟻，他們扮演了什麼角色?

And they sort of stand as a buffer in between

他們有點像介於在巢穴深處的工蟻

the ants working deep inside the nest and the ants working outside.

與在巢外的工蟻之間的緩衝角色，

And if you mark ants that are working outside, and dig up a colony,

如果你把那些在巢外的工蟻做上記號，然後挖開蟻巢，

you never see them deep down.

在蟻巢深處，你是找不到一隻螞蟻是有記號的。

So what's happening is that the ants work inside the nest when they're younger.

所以其實只有年輕的螞蟻會在蟻巢內工作，

They somehow get into this reserve.

他們以某種方式進入後備部隊，

And then eventually they get recruited to join this exterior workforce.

最後他們會被徵募並加入外面的工蟻；

And once they belong to the ants that work outside, they never go back down.

一旦他們被歸屬為外部的工蟻，他們就再也不會回到蟻巢的下層。

Now ants -- most ants, including these, don't see very well.

大部分的螞蟻，包括這些，他們的視力不怎麼好，

They have eyes, they can distinguish between light and dark,

雖然他們有眼睛能夠區分明暗，

but they mostly work by smell.

但是大部分他們依靠的是嗅覺。

So just to reinforce that what you might have thought

所以我想再強調，你們過去對蟻后的印象

about ant queens isn't true --

很可能是不正確，

you know, even if the queen did have the intelligence

即使蟻后是真的有智慧，

to send chemical messages through this whole network of chambers

能夠經由巢穴中的內部網路，傳送化學訊息

to tell the ants outside what to do,

去告訴所有外部的工蟻該做什麼，

there is no way that such messages could make it in time to see

但這些訊息也無法使那些工蟻像我們實際在巢外看到的那樣，

the shifts in the allocation of workers that we actually see outside the nest.

能夠迅速完成工作分派的調動與更替，

So that's one way that we know the queen isn't directing the behavior of the colony.

所以這是我們知道蟻后無法指揮整個蟻群的原因。

So when I first set out to work on task allocation,

所以當我開始研究它們的"任務分配"時，

my first question was, "What's the relationship

我第一個問題是"不同任務的分隊之間，

between the ants doing different tasks?

是否存在著某種關係?"

Does it matter to the foragers what the nest maintenance workers are doing?

修護分隊做的工作對覓食分隊有重要的意義嗎?

Does it matter to the midden workers what the patrollers are doing?"

巡邏分隊做的工作對堆肥分隊有重要的影響嗎?

And I was working in the context of a view of ant colonies in which each ant

而就我過去所知的觀點，每隻螞蟻

was somehow dedicated to its task from birth

似乎從出生就一直致力於它的任務，

and sort of performed independently of the others,

他們似乎明確知道他們的工作崗位在哪，

knowing its place on the assembly line.

並且能夠獨立執行。

And instead I wanted to ask, "How are the different task groups interdependent?"

不過我想問的是，"不同任務的分隊之間是如何相互依賴的?"

So I did experiments where I changed one thing.

所以我做了一些小實驗，

So for example, I created more work for the nest maintenance workers

比如說我在一大早，第一批維護分隊尚未行動時，

by putting out a pile of toothpicks near the nest entrance,

就放了一堆牙籤在蟻穴的入口附近，

early in the morning when the nest maintenance workers are first active.

以便增加維護分隊的工作份量。

This is what it looks like about 20 minutes later.

這是二十分鐘後的狀況，

Here it is about 40 minutes later.

而這是四十分鐘後的狀況，

And the nest maintenance workers just take all the toothpicks

最後維護分隊把所有的牙籤

to the outer edge of the nest mound and leave them there.

都堆放到巢穴的邊界去了。

And what I wanted to know was, "OK,

而我想知道的是，

here's a situation where extra nest maintenance workers were recruited --

在這種情形下，維護分隊要招募更多的工蟻來支援，

is this going to have any effect on the workers performing other tasks?"

而這會影響到其它分隊的工蟻嗎?

Then we repeated all those experiments with the ants marked.

然後我們重覆這個實驗，並且將工蟻們作上記號，

So here's some blue nest maintenance workers.

我們把維護分隊標記為藍色。

And lately we've gotten more sophisticated

接著我們再搞得複雜一些，

and we have this three-color system.

用三種顏色將工蟻

And we can mark them individually so we know which ant is which.

一隻隻的做標記，如此我們可以知道哪隻是哪隻。

We started out with model airplane paint

我們一開始是用模型飛機的油漆，

and then we found these wonderful little Japanese markers,

但後來我們發現日本的小麥克筆，

and they work really well.

非常適合用來做標記。

And so just to summarize the result,

我簡述一下我們的實驗結果，

well it turns out that yes, the different tasks are interdependent.

呃..沒錯，結果就是不同分隊的工蟻是彼此合作的，

So, if I change the numbers performing one task,

也就是說如果我改變了一個分隊的工作份量，

it changes the numbers performing another.

那麼另一個分隊的工蟻數量就會跟著改變。

So for example, if I make a mess

例如，我製造一些麻煩

that the nest maintenance workers have to clean up,

讓維護分隊去整理它，

then I see fewer ants out foraging.

那麼我就會看到覓食分隊的工蟻減少了，

And this was true for all the pair-wise combinations of tasks.

而所有的分隊都是這樣成對的消長組合。

And the second result, which was surprising to a lot of people,

第二個實驗結果可能會使很多人感到驚訝，

was that ants actually switch tasks.

那就是工蟻其實是會調換工作的，

The same ant doesn't do the same task over and over its whole life.

在工蟻的一生中，並不只是一直重覆做同樣的工作。

So for example, if I put out extra food, everybody else --

舉例來說，如果我多放一些食物，

the midden workers stop doing midden work and go get the food,

其它堆肥分隊的工蟻就會停止堆肥，而轉去搬食物，

they become foragers.

他們加入了覓食分隊!

The nest maintenance workers become foragers.

維護分隊的工蟻也會加入覓食分隊，

The patrollers become foragers.

巡邏分隊亦不例外。

But not every transition is possible. And this shows how it works.

不過並不是所有分隊之間都可以彼此轉換的，這是他們的運作方式，

Like I just said, if there is more food to collect, the patrollers, the midden workers,

就像我剛說的，如果有更多的食物要搜集，

the nest maintenance workers will all change to forage.

無論是哪個分隊都會全力支援覓食分隊。

If there's more patrolling to do --

如果我製造了一些擾亂，

so I created a disturbance, so extra patrollers were needed --

增加了巡邏分隊的工作量，那麼就需要更多的工蟻支援，

the nest maintenance workers will switch to patrol.

這時維護分隊的工蟻就會加入巡邏分隊。

But if more nest maintenance work is needed --

但同時若也有工作需要維護分隊來完成，

for example, if I put out a bunch of toothpicks --

舉例來說，我又放了一大堆牙籤，

then nobody will ever switch back to nest maintenance,

這時就沒有其他分隊會調動回來做這些工作，

they have to get nest maintenance workers from inside the nest.

這時他們就不得不出動巢穴內的工蟻。

So foraging acts as a sink, and the ants inside the nest act as a source.

所以覓食任務是勞力的集中站，蟻穴內的工蟻便是勞力來源。

And finally, it looks like each ant is deciding

最後，看起來每隻螞蟻似乎

moment to moment whether to be active or not.

時時刻刻都在決定是否需要採取行動。

So, for example, when there's extra nest maintenance work to do,

所以，假如當維護分隊有額外工作需要支援時，

it's not that the foragers switch over. I know that they don't do that.

覓食分隊是不會前來支援的，我知道他們不會這麼做，

But the foragers somehow decide not to come out.

但是他們以某種方式決定不前來支援。

And here was the most intriguing result: the task allocation.

而這正是最吸引人的部分：任務分配。

This process changes with colony age, and it changes like this.

這個過程會隨著蟻群的年齡而改變，這是它們改變的方式。

When I do these experiments with older colonies --

當我對較成熟的蟻群做這些實驗時，

so ones that are five years or older --

就是那些五歲以上的蟻群，

they're much more consistent from one time to another

他們顯然能一直保持著一致的調動模式，

and much more homeostatic. The worse things get,

而且協調得很好。即使當最糟的事情發生，

the more I hassle them, the more they act like undisturbed colonies.

我愈騷擾他們，他們表現的愈是泰然自若；

Whereas the young, small colonies --

然而較年輕且小的蟻群，

the two-year-old colonies of just 2,000 ants -- are much more variable.

大約是兩歲左右，規模約二千隻工蟻的蟻群，相對而言則變化較大。

And the amazing thing about this is that an ant lives only a year.

而最令人不敢相信的是這些工蟻的壽命只有一年，

It could be this year, or this year.

可能是這年，也可能是那年，

So, the ants in the older colony that seem to be more stable

所以在成熟蟻群看起來比較穩定的工蟻，

are not any older than the ants in the younger colony.

其實也沒有比年輕蟻群的工蟻老，

It's not due to the experience of older, wiser ants.

成熟蟻群的工蟻並不是有比較多的經驗或者更聰明，

Instead, something about the organization

相反的，一定是某種組織方式

must be changing as the colony gets older.

會隨著蟻群成長而跟著改變，

And the obvious thing that's changing is its size.

最明顯的就是蟻群大小的改變。

So since I've had this result, I've spent a lot of time trying to figure out

所以自從我知道了這樣的結果後，我花了很多時間試著去了解

what kinds of decision rules -- very simple, local, probably olfactory, chemical

螞蟻可能使用的方法，一定是簡單、局部、嗅覺或化學之類的法則，

rules could an ant could be using, since no ant can assess the global situation --

因為沒有一隻螞蟻可以評估整體的狀況，

that would have the outcome that I see,

但他們卻表現出那種有效的組織方式。

these predictable dynamics, in who does what task.

而誰該做什麼工作，是可以預測的，

And it would change as the colony gets larger.

還會隨著蟻群成長而改變。

And what I've found out is that ants are using a network of antennal contact.

我所發現的是，工蟻是藉由觸角接觸來建立網路的，

So anybody who's ever looked at ants has seen them touch antennae.

看過螞蟻的人都知道它們會用觸角彼此接觸，

They smell with their antennae.

他們可以用觸角聞嗅氣味。

When one ant touches another, it's smelling it,

每當它們用觸角接觸，就是在聞味道，

and it can tell, for example, whether the other ant is a nest mate

而且這味道可以使彼此知道是自己人，

because ants cover themselves and each other, through grooming,

因為螞蟻會彼此利用梳毛的方式，

with a layer of grease, which carries a colony-specific odor.

為對方覆蓋上一層具有蟻群獨特氣味的油脂。

And what we're learning is that an ant uses the pattern of its antennal contacts,

而我們研究的便是螞蟻各種觸角接觸的模式，

the rate at which it meets ants of other tasks, in deciding what to do.

從不同分隊的工蟻的觸角接觸頻率，可以決定它們該做什麼，

And so what the message is, is not any message

它們一隻接著一隻所傳送出去的內容，

that they transmit from one ant to another, but the pattern.

並不是訊息，而是模式，

The pattern itself is the message.

模式本身就是訊息，

And I'll tell you a little bit more about that.

我會再加以解釋。

But first you might be wondering:

但是一開始你們也許會想知道，

how is it that an ant can tell, for example, I'm a forager.

螞蟻是如何表明自己身分的，比如說我是覓食分隊的，

I expect to meet another forager every so often.

我會認為我遇到的應該都是覓食分隊的工蟻，

But if instead I start to meet a higher number of nest maintenance workers,

但是如果相反地，如果我開始遇到很多維護分隊的工蟻，

I'm less likely to forage.

我現在就不太可能是在覓食。

So it has to know the difference between

所以我們必須知道如何分辨覓食分隊

a forager and a nest maintenance worker.

與維護分隊之間的差異，

And we've learned that, in this species --

而我們已經知道的是，這種螞蟻--

and I suspect in others as well --

我懷疑其它種類的螞蟻也是一樣--

these hydrocarbons, this layer of grease on the outside of ants,

覆蓋在螞蟻身上的油脂中的碳氫化合物，

is different as ants perform different tasks.

會依不同任務的工蟻而有所不同。

And we've done experiments that show that

從我們已經做的實驗顯示，

that's because the longer an ant stays outside,

在外面待得愈久的螞蟻，

the more these simple hydrocarbons on its surface change,

它們表皮上的碳氫化合物就會有愈大的改變，

and so they come to smell different by doing different tasks.

所以他們會聞起來不一樣。

And they can use that task-specific odor in cuticular hydrocarbons --

而這種來自表皮碳氫化合物的特定任務氣味，

they can use that in their brief antennal contacts to somehow

在他們做短暫的觸角接觸時，會被用來

keep track of the rate at which they're meeting ants of certain tasks.

記錄他們與某個分隊工蟻的接觸速度，

And we've just recently demonstrated this

這是我們最近才剛證實的。

by putting extract of hydrocarbons on little glass beads,

我們把一些很小的玻璃珠沾上碳氫化合物，

and dropping the beads gently down into the nest entrance at the right rate.

以正確的速度把這些珠子輕輕的從蟻巢入口放入，

And it turns out that ants will respond to the right rate of contact

結果那些工蟻也以同樣的速度來回應接觸

with a glass bead with hydrocarbon extract on it,

那些沾有碳氫化合物的珠子，

as they would to contact with real ants.

就跟他們接觸其它真實的工蟻一般。

So I want now to show you a bit of film --

我現在要播放一小段影片，

and this will start out, first of all, showing you the nest entrance.

開始了，首先你看到的是蟻巢的入口，

So the idea is that ants are coming in and out of the nest entrance.

這些螞蟻正從蟻巢的入口不斷地進進出出，

They've gone out to do different tasks, and the rate at which they meet

他們出去完成不同的任務，而當他們進出入口時，

as they come in and out of the nest entrance determines, or influences,

他們接觸的速度會決定或影響

each ant's decision about whether to go out, and which task to perform.

每一隻螞蟻的決定，看是否要出去執行什麼任務。

This is taken through a fiber optics microscope. It's down inside the nest.

這是透過光纖顯微鏡所拍攝到的蟻巢內部，

In the beginning you see the ants

一開始你會看到這些工蟻

just kind of engaging with the fiber optics microscope.

好像對這光纖顯微鏡很感興趣，

But the idea is that the ants are in there,

但是我要讓你們看的是，那些工蟻

and each ant is experiencing a certain flow of ants past it --

正持續地與它身旁竄流過去的工蟻們

a stream of contacts with other ants.

源源不斷的相互接觸，

And the pattern of these interactions determines

而這些互動的模式會決定

whether the ant comes back out, and what it does when it comes back out.

他們是否要再出去，以及出去做什麼。

You can also see this in the ants just outside the nest entrance like these.

你也可以在蟻巢的外面看到這些工蟻，

Each ant, then, as it comes back in, is contacting other ants.

每一隻回來蟻巢的工蟻，正在與其它的工蟻做接觸；

And the ants that are waiting just inside the nest entrance

而蟻巢入口處的工蟻則正在等待

to decide whether to go out on their next trip,

這些剛回來的工蟻們，並與他們逐一接觸，

are contacting the ants coming in.

以決定是否前往下一個旅程。

So, what's interesting about this system is that it's messy.

所以這個系統有趣的地方在於，它是亂無章法的，

It's variable. It's noisy. And, in particular, in two ways.

它是變化無常的，尤其還有兩種不確定因子，

The first is that the experience of the ant -- of each ant -- can't be very predictable.

第一，每隻工蟻的經驗是不能夠預測的，

Because the rate at which ants come back depends on

因為工蟻們回來時的速度

all the little things that happen to an ant as it goes out and does its task outside.

取決於他們在外面工作時，遭遇到的所有大小事；

And the second thing is that an ant's ability to assess this pattern

第二，每隻工蟻僅能對這種模式做粗略的評估，

must be very crude because no ant can do any sophisticated counting.

因為工蟻並不能夠做任何複雜的計數。

So, we do a lot of simulation and modeling, and also experimental work,

所以我們建立了很多模型來模擬，也做了很多實驗，

to try to figure out how those two kinds of noise combine to,

我們想試著去了解如何把這兩種不確定因子結合，

in the aggregate, produce the predictable behavior of ant colonies.

以產生可預期的蟻群集體行為。

Again, I don't want to say that this kind of haphazard pattern of interactions

再一次強調，我不是說這種無秩序般的互動模式

produces a factory that works with the precision and efficiency of clockwork.

可以製造出工廠般機械化的精準及效率，

In fact, if you watch ants at all, you end up trying to help them

事實上，如果你仔細觀察它們，你最後會想幫他們一把

because they never seem to be doing anything

因為它們的工作看起來總是

exactly the way that you think that they ought to be doing it.

無法達到應有的水準，

So it's not really that out of these haphazard contacts, perfection arises.

所以這種無秩序的接觸方式，並不能完美的達成所有任務，

But it works pretty well.

但是它仍然運作的不錯，

Ants have been around for several hundred million years.

螞蟻已如此生存了數十億年，

They cover the earth, except for Antarctica.

除了南極洲，他們幾乎遍佈整個地球，

Something that they're doing is clearly successful enough

這代表他們一定有什麼過人之處，

that this pattern of haphazard contacts, in the aggregate,

能夠利用這種無秩序的接觸方式，

produces something that allows ants to make a lot more ants.

讓他們能夠繁衍出更多的螞蟻。

And one of the things that we're studying is how natural selection

而我們正在研究的問題之一，

might be acting now to shape this use of interaction patterns --

是大自然如何選擇塑造出這種互動模式，

this network of interaction patterns --

如何塑造出這種

to perhaps increase the foraging efficiency of ant colonies.

能讓蟻群的覓食效率提高的互動網路。

So the one thing, though, that I want you to remember about this

不過有件事我希望你們還記得，

is that these patterns of interactions

就是這種互動的模式

are something that you'd expect to be closely connected to colony size.

是能夠隨著蟻群大小變化而有所調整的。

The simplest idea is that when an ant is in a small colony --

最簡單的例子，就是小蟻群中的工蟻

and an ant in a large colony can use the same rule,

和大蟻群中的工蟻用的是同一種法則，

like "I expect to meet another forager every three seconds."

大蟻群中的工蟻，可能每三秒就會接觸一隻其它覓食分隊的工蟻，

But in a small colony, it's likely to meet fewer foragers,

而小蟻群中的工蟻，接觸的頻率則可能低的多，

just because there are fewer other foragers there to meet.

只因為小蟻群的覓食分隊規模比較小，

So this is the kind of rule that, as the colony develops and gets older and larger,

所以這種法則在蟻群成長變大時，

will produce different behavior in an old colony and a small young one.

蟻群的行為亦會跟著調適而有所不同。

Thank you.

謝謝。

(Applause)

(鼓掌)