Deborah Gordon: The emergent genius of ant colonies

Prevoditelj: Ivan Stamenković Recezent: Senzos Osijek

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

Ja proučavam mrave, jer volim promišljati o tome kako organizacije rade.

And in particular, how the simple parts of organizations

I sada osobito, kako jednostavni dijelovi organizacija

interact to create the behavior of the whole organization.

surađuju da bi stvorili ponašanje cijele organizacije.

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

Dakle, mravlje kolonije dobar su primjer takve organizacije,

and there are many others. The web is one.

i postoje mnoge druge. Paukova mreža je jedna od njih.

There are many biological systems like that --

Postoje mnogi biološki sustavi kao što je taj --

brains, cells, developing embryos.

mozgovi, stanice, embriji u razvoju.

There are about 10,000 species of ants.

Postoji otprilike 10000 vrsta mravi.

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

Svi oni žive u kolonijama od jedne ili nekoliko kraljica,

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

a svi mravi koje vidite da šetaju uokolo su sterilne ženske radilice.

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

I sve mravlje kolonije zajednički imaju nedostatak centralne kolone.

Nobody tells anybody what to do.

Nitko nikome ne govori što da čini.

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

Kraljica samo polaže jaja. Ne postoji upravljanje.

No ant directs the behavior of any other ant.

Nijedan mrav ne upravlja drugim mravom.

And I try to figure out how that works.

I pokušavam shvatiti kako to radi.

And I've been working for the past 20 years

I radim posljednjih 20 godina

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

na populaciji mrava koji jedu sjemenje u jugoistočnoj Arizoni.

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

Ovo je mjesto gdje proučavam. Ovo je stvarno slika mrava,

and the rabbit just happens to be there.

i zec je slučajno naišao.

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

I ovi mravi zovu se žeteoci jer jedu sjemenke.

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

Ovo je gnijezdo zrele kolonije, i ovdje je ulaz u gnijezdo.

And they forage maybe for about 20 meters away,

I skupljaju u krugu od 20 metara,

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

skupljaju sjemenke, i nose ih u gnijezdo, gdje ih pohranjuju.

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

I idem tamo da napravim kartu područja izučavanja.

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

Ovo je samo cesta, i nije tako velika.

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

Oko 250 metara s jedne, 400 metara s druge.

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

I svaka kolonija ima ime, koje je broj,

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

koje je napisano na kamenu. I idem tamo svake godine

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

i tražim sve kolonije koje su živjele godinu prije,

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

i pokušavam shvatiti koje su uginule, i dodati nove.

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

I radeći to, znam koliko su stare.

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

I zbog toga, mogla sam proučavati kako se njihovo ponašanje mijenja

as the colony gets older and larger.

kako kolonija stari i raste.

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

Želim vam reći nešto o životnom ciklusu kolonije.

Ants never make more ants; colonies make more colonies.

Mravi nikad ne rade nove mrave, kolonije rade nove kolonije.

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

I to rade svake godine šaljući razmnažatelje --

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

to su oni s krilima -- na let parenja.

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

Tako da sveke godine, istog dana -- i misterija je kako se to događa --

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

svaka kolonija šalje svoju djevičansku, neparenu kraljicu i mužjake,

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

i oni svi lete na isto mjesto. I pare se.

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

I ovo je mlada kraljica. Ovo su joj krila.

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

I u procesu je parenja s mužjakom,

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

i tu je još jedan mužjak koji čeka red.

Often the queens mate more than once.

Često se kraljice pare više puta.

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

I nakon toga, svi mužjaci ugibaju. To je to za njih.

(Laughter)

(Smijeh)

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

I onda oplođene kraljice negdje lete i odlažu krila,

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

kopaju rupu i ulaze u nju, te polažu jaja.

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

I živjet će 15 do 20 godina, nastavljajući leći jaja

using the sperm from that original mating.

koristeći spermu iz originalnog parenja.

So the queen goes down in there.

Kraljica ode tamo dolje.

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

Polaže jaja, hrani ličinke -- mrav počinje kao jaje, onda je ličinka.

She feeds the larvae by regurgitating from her fat reserves.

Hrani ličinke koristeći svoje zalihe masti.

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

Onda, čim se mravi -- prva grupa -- izlegu,

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

oni su ličinke. Potom su kukuljice. A nakon toga odrasli mravi.

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

Izlaze van, donose hranu, iskapaju gnijezdo

and the queen never comes out again.

i kraljica nikad više ne ide van.

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

Ovo je jednogodišnja kolonija -- ovo je broj 536.

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

Tu je ulaz u gnijezdo i olovka za mjeru.

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

Ovu koloniju kraljica osnovala prošlog ljeta.

This is a three-year-old colony.

Ovo je trogodišnja kolonija.

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

Ovdje je ulaz u gnijezdo, a ovdje je olovka radi mjere.

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

Rade humak, hrpu otpadaka -- najviše ljuske sjemenki koje jedu.

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

Ovo je petogodišnja kolonija. Ovo je ulaz, a ovo je olovka za mjeru.

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

Do ove veličine narastu, otprilike metar.

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

A ovo je kako se veličina kolonije i broj mrava radnika mijenja --

so this is about 10,000 worker ants --

tako da je ovo oko 10000 mrava radnika --

changes as a function of colony age, in years.

kako se mijenja, s godinama, funkcija kolonije.

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

Tako da počinje s nula mrava, samo kraljicom osnivačicom,

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

raste do veličine od 10 do 12 tisuća mrava kada kolonija ima pet godina.

And it stays that size until the queen dies

I ostaje te veličine dok ne ugine kraljica

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

i nema nikoga da radi nove mrave, kada ima otprilike 15 ili 20 godina.

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

I kada dosegnu ovu stabilnu veličinu, u broju mrava,

that they start to reproduce.

oni se počinju razmnožavati.

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

To jest, slati više krilatih kraljica i mužjaka na let za parenje te godine.

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

I znam kako se veličina kolonije mijenja kao funkcija starosti kolonije

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

jer sam iskopala kolonije poznate starosti i prebrojala sve mrave. (Smijeh)

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

To nije nazanimljiviji dio ovog istraživanja, iako je zanimljiv.

(Laughter)

(Smijeh)

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

Pravo pitanje kod ovih mrava je zapravo raspodjela zadataka.

That's not just how is the colony organized,

To nije samo kako je kolonija organizirana,

but how does it change what it's doing?

ali kako se mijenja, što radi?

How is it that the colony manages to adjust

Kako to kolonija prilagođava

the numbers of workers performing each task as conditions change?

broj radnika koji rade neki zadatak kako se mijenjaju uvjeti?

So, things happen to an ant colony.

Dakle, stvari se događaju koloniji mrava.

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

Kada ljeti kiši, nastaju poplave u pustinji.

There's a lot of damage to the nest,

Gnijezdo se dosta oštećuje,

and extra ants are needed to clean up that mess.

i dodatni mravi potrebni su da se počisti nered.

When extra food becomes available --

Kada dodatna hrana postane dostupna --

and this is what everybody knows about picnics --

i ovo je što svi znaju o piknicima --

then extra ants are allocated to collect the food.

dodatni mravi su raspoređeni da skupljaju hranu.

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

Pa, iako nitko nikom ne govori što da čini, kako to da

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

kolonija prilagođuje broj radnika koji obavlja svaki zadatak?

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

I to je proces koji zovem raspoređivanje zadataka.

And in harvester ants, I divide the tasks

I kod mrava skupljača, dijelim zadatke

of the ants I see just outside the nest

mravi koje vidim odmah izvan gnijezda

into these four categories: where an ant is foraging,

u ove četiri kategorije: kada mrav skuplja,

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

kada se nalazi na stazi skupljanja, tražeći hranu ili noseći hranu natrag.

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

Patrolni -- ovo je povećalo --

are an interesting group that go out early in the morning

su zanimljiva grupa koja idea van ujutro,

before the foragers are active.

prije nego su skupljači aktivni.

They somehow choose the direction that the foragers will go,

Odabiru smjer kojim će skupljači ići,

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

i vraćajući se -- samo vraćajući se --

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

kažu skupljačima da je sigurno ići van.

Then the nest maintenance workers work inside the nest,

Onda mravi koji održavaju rade unutar gnijezda,

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

i htjela sam reći kako gnijezda izgledaju poput kuće Billa Lishmana.

That is, that there are chambers inside,

To jest, unutra postoje komore,

they line the walls of the chambers with moist soil

a zidovi komora su prekriveni vlažnom zemljom

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

i ona se suši u površinu poput nepečene opeke.

It also looks very similar to some of the cave dwellings

I također izgleda kao nastambe u špiljama

of the Hopi people that are in that area.

Hopi naroda koji živi u tom području.

And the nest maintenance workers do that inside the nest,

I održavači gnjezda to rade unutar njega,

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

i izlaze iz gnijezda noseći komadiće suhog tla.

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

Tako da vidite održavače kako izlaze sa malo pijeska,

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

odlažu ga, okreću se i ulaze unutra.

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

I napokon, srednji radnici stavljaju neku teritorijalnu kemikaliju u otpad.

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

Tako da vidite srednje radnike kako rade hrpu otpada.

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

Jednog dana je tu, a drugog dana

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

pomaknut će je tamo, i vratit natrag.

So that's what the midden workers do.

To je ono što rade srednji radnici.

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

I ove četiri skupine su mravi izvan gnijezda.

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

To je samo 25 posto kolonije i to su najstariji mravi.

So, an ant starts out somewhere near the queen.

Dakle, mrav počinje blizu kraljice.

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

I kada iskapamo gnijezdo vidimo kako su duboki

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

otprilike koliko je kolonija široka, otprilike metar duboko za velika gnijezda.

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

I onda postoji još jedan dugi tunel i komora, gdje nalazimo kraljicu,

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

poslije osam sati udaranja stijene sa cepinom.

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

Ne mislim da je komora evoluirala zbog mene i moje motike

and my crew of students with pickaxes,

i mojih studenata s cepinima,

but instead because when there's flooding,

već zato ako bude poplave,

occasionally the colony has to go down deep.

ponekad kolonija mora otići duboko.

So there's this whole network of chambers.

Tako da postoji cijela mreža komora.

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

Kraljica je tu negdje, samo polaže jaja.

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

Postoje ličinke i one troše većinu hrane.

And this is true of most ants --

I ovo je istinito za većinu mrava --

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

da mravi koji se šetaju ne jedu puno.

They bring it back and feed it to the larvae.

Oni donose hranu i hrane ličinke.

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

Kada skupljači dođu s hranom, bacaju je u gornju komoru,

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

i drugi mravi dolaze iz zemlje, uzimaju hranu,

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

nose je natrag, čiste sjemenke i gomilaju ih.

There are nest maintenance workers working throughout the nest.

Postoje mravi za održavanje gnijezda kroz cijelu nastambu.

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

I čudno, i zanimljivo, izgleda da u svakom trenutku

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

pola mrava u koloniji ne radi ništa.

So, despite what it says in the Bible,

Tako da, bez obzira na pouku iz Bibilije,

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

o znate, "Pogledajte mrava, ljenjivci,"

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

zapravo, ti mravi su rezerva.

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

Ako se nešto dogodi -- i nikad se ništa takvo nije dogodilo,

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

ali ja gledam samo 20 godina --

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

da se nešto dogodi, možda svi izađu ako budu potrebni.

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

Ali zapravo, većinom se samo nalaze tamo.

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

I mislim da je to zanimljivo pitanje --

what is there about the way the colony is organized

što ima u organizaciji kolonije

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

što bi dalo funkciju rezervi mrava koja ne radi ništa?

And they sort of stand as a buffer in between

I koriste se kao sigurnosna zona između

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

mrava koji rade duboko u gnijezdu i onih koji rade vani.

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

I ako označite mrave koji rade vani, i otkopate koloniju,

you never see them deep down.

nikad ih ne vidite duboko dolje.

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

Ti mravi unutar gnijezda, kada su mlađi.

They somehow get into this reserve.

Oni nekoako dolaze u tu rezervu.

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

I nekad ih regrutiraju da idu u vanjsku radnu snagu.

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

I kad pripadaju mravima koji rade vani, nikad se ne vraćaju dolje.

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

Sad mravi -- većina mravi, pa i ovi, ne vide dobro.

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

Imaju oči, mogu razaznati svjetlost i tamu,

but they mostly work by smell.

ali rade najčešće mirisom.

So just to reinforce that what you might have thought

Samo da podupremo ono što ste možda mislili

about ant queens isn't true --

o kraljici nije istina --

you know, even if the queen did have the intelligence

znate, čak i da ima inteligenciju

to send chemical messages through this whole network of chambers

da pošalje kemijske poruke kroz ovu mrežu komora

to tell the ants outside what to do,

kako bi rekla mravima vani što da čine,

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

nema načina da takva poruka stigne na vrijeme da bi se vidjela

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

promjena u alokaciji radnika, koju vidimo izvan gnijezda.

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

To je način za koji znamo da nije korišten kako bi se upravljalo kolonijom.

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

Kada sam prvi put počela raditi na raspodjeli zadataka,

my first question was, "What's the relationship

moje prvo pitanje bilo je, "Koja je veza

between the ants doing different tasks?

između mrava koji rade različite zadatke?

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

Da li je važno za skupljače ono što čine radnici na održavanju?

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

Je li važno srednjim radnicima što rade izviđači?"

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

I radila sam u kontekstu gledanja na koloniju u kojoj svaki mrav

was somehow dedicated to its task from birth

ima ulogu dodijeljenu pri rođenju

and sort of performed independently of the others,

i djeluje nezavisno od drugih,

knowing its place on the assembly line.

znajući svoje mjesto u proizvodnoj liniji.

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

I umjesto toga htjela sam pitati, "Kako su različite grupe međuovisne?"

So I did experiments where I changed one thing.

Radila sam eksperimente gdje sam radila jednu stvar.

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

Na primjer, stvorila sam više posla za radnike na održavanju

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

stavljajući hrpu čačkalica pored ulaza u gnijezdo,

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

rano ujutro kada su radnici prvi aktivni.

This is what it looks like about 20 minutes later.

Ovako to izgleda 20 minuta kasnije.

Here it is about 40 minutes later.

Ovo je otprilike 40 minuta kasnije.

And the nest maintenance workers just take all the toothpicks

I radnici na održavanju samo odnesu čačkalice

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

na vanjski rub humka gnijezda i ostave ih tamo.

And what I wanted to know was, "OK,

I ono što sam htjela znati je, "Ok,

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

ovdje je regrutiran dodatni broj radnika --

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

hoće li to utjecati na radnike koji rade druge stvari?"

Then we repeated all those experiments with the ants marked.

Onda smo ponovili sve te eksperimente sa označenim mravima.

So here's some blue nest maintenance workers.

Evo nekoliko plavih radnika na održavanju.

And lately we've gotten more sophisticated

I odnedavna smo postali profinjeniji

and we have this three-color system.

i imamo ovaj sustav od tri boje.

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

I možemo ih pojedinačno označit kako bi znali koji je mrav koji.

We started out with model airplane paint

Počeli smo sa bojom za makete aviona

and then we found these wonderful little Japanese markers,

i onda smo pronašli ove japanske markere,

and they work really well.

i oni jako dobro rade.

And so just to summarize the result,

I samo da sumiramo rezultat,

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

ispada da su međuovsni različiti zadatci.

So, if I change the numbers performing one task,

Tako da promjena broja radnika u jednom zaadatku,

it changes the numbers performing another.

mijenja broj radnika koji obavljaju drugi.

So for example, if I make a mess

Na primjer, ako napravim nered

that the nest maintenance workers have to clean up,

koji radnici na održavanju moraju očistiti,

then I see fewer ants out foraging.

onda manje mravi skuplja hranu.

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

I ovo je bilo istinito za sve parne kombinacije zadataka.

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

I drugi rezultat, koji je iznenađujuć za puno ljudi,

was that ants actually switch tasks.

je taj da mravi mijenjaju zadatke.

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

Isti mrav ne radi isti zadatak cijeli svoj život.

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

Na primjer, ako stavim dodatne hrane, svi ostali --

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

srednji radnici izlaze po hranu,

they become foragers.

postaju skupljači.

The nest maintenance workers become foragers.

Održavači gnijezda postaju skupljači.

The patrollers become foragers.

Ivzidnici postaju skupljači.

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

Ali svako prebacivanje je moguće. I to pokazuje kako to radi.

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

Kao što sam rekao, ako postoji više hrane, svi radnici

the nest maintenance workers will all change to forage.

će se prebaciti na skupljanje.

If there's more patrolling to do --

Ako treba još izviđati --

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

stvorila sam poremećaj, pa je trebalo još izviđača --

the nest maintenance workers will switch to patrol.

radnici na održavanju se prebacuju u izviđače.

But if more nest maintenance work is needed --

Ali ako treba još radnika za održavanje --

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

na primjer, ako postavim hrpu čačkalica --

then nobody will ever switch back to nest maintenance,

nitko se neće vratiti na održavanje,

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

nego će doći radnici iz dubine gnijezda.

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

Tako da je skupljanje kao odvod, a mravi u gnijezdu su izvor.

And finally, it looks like each ant is deciding

I napokon, čini se da svaki mrav odlučuje

moment to moment whether to be active or not.

iz trenutka u trenutak o aktivnosti.

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

Na primjer, ako ima više posla u održavanju,

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

skupljači se neće prebaciti. Znam da to ne čine.

But the foragers somehow decide not to come out.

Ali skupljači nekako odlučuju ne izaći.

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

I ovdje je najzanimljiviji rezultat: raspodjela zadataka.

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

Ovaj proces se mijenja sa starosti kolonije, na ovaj način.

When I do these experiments with older colonies --

Kada radim ove eksperimente sa starijim kolonijama --

so ones that are five years or older --

sa starijima od pet godina --

they're much more consistent from one time to another

puno su dosljednije od jednog trenutka do drugog

and much more homeostatic. The worse things get,

i puno homeostatskije. Što su stvari gore,

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

više ih mučim, više se ponašaju kao neuznemirene kolonije.

Whereas the young, small colonies --

Dok mlade, malene kolonije --

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

dvogodišnje kolonije sa 2000 mravi -- više variraju.

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

I zadivljujuća stvar oko toga je da mrav živi samo godinu dana.

It could be this year, or this year.

To je možda ova, ili ova godina.

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

Dakle, mravi u starijim kolonijama koji se čine stabilniji

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

nisu samo stariji od mrava u mlađoj koloniji.

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

Ne radi se o iskustvu starijih, mudrijih mrava.

Instead, something about the organization

Umjesto toga, nešto u organizaciji

must be changing as the colony gets older.

mora se mjenjati kako kolonija stari.

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

I očita stvar koja se mijenja je veličina.

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

Otkada sam imao ovaj rezultat, potrošila sam puno vremena pokušavajući shvatiti

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

koja pravila za odluke -- jednostavna, lokalna, kemijska

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

pravila može mrav koristiti, jer nijedan mrav ne može ocijeniti globalnu situaciju --

that would have the outcome that I see,

koja bi imala ishod koji vidim,

these predictable dynamics, in who does what task.

ovu predvidljivu dinamiku, tko radi što.

And it would change as the colony gets larger.

I mijenjalo bi se kako kolonija raste.

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

I ono što sam našla je da mravi koriste mrežu antenskog kontakta.

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

Tko god je gledao mrave zna da se diraju antenama.

They smell with their antennae.

Mirišu antenama.

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

Kada jedan mrav dira drugog, miriše ga,

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

i može reći je li taj mrav iz istog gnijezda

because ants cover themselves and each other, through grooming,

jer se mravi prekrivaju, kroz čišćenje,

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

slojem masti koji nosi miris kolonije.

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

I ono što učimo je da mrav koristi uzorak svojih kontakata s antenama,

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

brzinu kojom sreće druge mrave, u odluci što činiti dalje.

And so what the message is, is not any message

I poruka je, ne ona poruka koju

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

prenose od jednog do drugog, već uzorak.

The pattern itself is the message.

Sam uzorak je poruka.

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

I reći ću vam nešto o tome.

But first you might be wondering:

Ali prvo se možda pitate:

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

kako to da mrav može znati da sam skupljač

I expect to meet another forager every so often.

Očekujem da ću svako toliko sresti skupljača.

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

Ali ako se umjesto toga susrećem s puno više radnika,

I'm less likely to forage.

puno su manje šanse da ću skupljati.

So it has to know the difference between

Zato mora znati razliku između

a forager and a nest maintenance worker.

skupljača i održavača.

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

I naučili smo da ovo, u toj vrsti --

and I suspect in others as well --

i sumnjam u drugima također --

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

ova mast na mravu,

is different as ants perform different tasks.

je drugačija kod mrava koji rade različite zadatke.

And we've done experiments that show that

I radili smo eksperimente koji to pokazuju

that's because the longer an ant stays outside,

jer što je mrav duže vani

the more these simple hydrocarbons on its surface change,

to se jednostavni ugljikovodici na površini mijenjaju,

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

i mirišu drugačije jer rade drugačije stvari.

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

I mogu koristiti taj miris --

they can use that in their brief antennal contacts to somehow

mogu ga koristiti u kratkom kontaktu antenama --

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

pratiti koliko često susreću mrave na određenom zadatku.

And we've just recently demonstrated this

I to smo nedavno demonstrirali

by putting extract of hydrocarbons on little glass beads,

stavljajući ekstrakte ugljikovodika na male staklene kuglice

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

i bacajući kuglice kroz ulaz pravim tempom.

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

I ispada da će mravi reagirati na pravi tempo kontakta

with a glass bead with hydrocarbon extract on it,

sa staklenom kuglicom s ekstraktom

as they would to contact with real ants.

kao da su kontaktu s pravim mravima.

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

Želim vam pokazati snimku --

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

ovako to počinje, pokazujem ovam ulaz.

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

Ideja je da mravi ulaze i izlaze iz gnijezda.

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

Izlaze da bi radili različite stvari, i tempo kojim se susreću

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

kako ulaze i izlaze utječe ili određuje,

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

odluku o tome gdje mrav ide i što radi.

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

Ovo je snimano kroz optički mikroskop. Nalazi se u gnijezdu.

In the beginning you see the ants

Na početku vidite mrave

just kind of engaging with the fiber optics microscope.

kako se obaziru na mikroskop.

But the idea is that the ants are in there,

Ali ideaja je da su mravi ondje

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

i svaki mrav osjeća tok mrava pored sebe --

a stream of contacts with other ants.

tok kontakta s drugim mravima.

And the pattern of these interactions determines

I uzorak tih interakcija određuje

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

hoće li izaći, i što radi kad ide van.

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

Također možete vidjeti istu stvar u mravima kod izlaza iz gnijezda.

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

Svaki mrav, dok se vraća unutra je u doticaju s drugim mravima.

And the ants that are waiting just inside the nest entrance

I mravi koji čekaju na ulazu u gnijezdo

to decide whether to go out on their next trip,

kako bi odlučili gdje će,

are contacting the ants coming in.

u kontaktu su s mravima koji ulaze.

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

Zanimljivo je da je taj sustav neuredan.

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

Varijabilan je i bučan. I to na dva načina.

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

Prvi je da je iskustvo svakog mrava nepredvidljivo.

Because the rate at which ants come back depends on

Jer tempo kojim se mravi vraćaju ovisi o

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

malim stvarima koje se događaju mravu dok je vani na zadatku.

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

I druga stvar je da je mravlja sposobnost da ocijeni uzorak

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

vrlo jednostavna jer mrav ne može brojati.

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

Tako da radimo puno simuliranja, modeliranja i eksperimenata,

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

kako bi otkrili kako se ove dvije vrste buke kombiniraju,

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

i kako stvaraju predvidljivo ponašanje kolonija mrava.

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

Ne želim reći da ovaj uzorak interakcija

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

stvara tvornicu koja radi savršeno.

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

Zapravo, ako gledate mrave, želite im pomoći

because they never seem to be doing anything

jer se uvijek čini da ne rade ništa

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

onako kako vi mislite da bi trebali.

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

Tako da iz ovoga ne proizlazi savršenstvo.

But it works pretty well.

Ali radi dosta dobro.

Ants have been around for several hundred million years.

Mravi su tu nekoliko stotina milijuna godina.

They cover the earth, except for Antarctica.

Prekrivaju zemlju, osim Antartike.

Something that they're doing is clearly successful enough

Nešto što rade je očito dovoljno uspješno,

that this pattern of haphazard contacts, in the aggregate,

da ovaj uzorak interakcija

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

stvara nešto što dozvoljava da mravi rade puno novih mrava.

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

I jedna od stvari koje proučavamo su kako prirodna selekcija

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

djeluje da bi oblikovala uporabu ovih uzoraka interakcija --

this network of interaction patterns --

ovu mrežu uzoraka interakcija --

to perhaps increase the foraging efficiency of ant colonies.

da bi povećala učinkovitost skupljanja mravljih kolonija.

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

Ali želim da od ovoga zapamtite ovo:

is that these patterns of interactions

ovi uzorci interakcija

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

su nešto što bi trebalo biti usko vezano s veličinom kolonije.

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

Najjednostavnija ideja je da kada je mrav u malenoj koloniji --

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

a i mravi u velikima koriste isto pravilo,

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

kao "Očekujem svake tri sekunde sresti novog skupljača."

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

Ali u maloj koloniji srest će puno manje skupljača,

just because there are fewer other foragers there to meet.

jer je manje skupljača za sresti.

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

To je pravilo, da kako kolonija stari i raste,

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

stvarat će drugačije ponašanje u staroj i mladoj koloniji.

Thank you.

Hvala vam.

(Applause)

(Pljesak)