Svante Pääbo: DNA clues to our inner neanderthal

Prevoditelj: Senzos Osijek Recezent: Tilen Pigac - EFZG

What I want to talk to you about

Ono o čemu vam želim govoriti

is what we can learn from studying the genomes

je što možemo naučiti iz proučavanja genoma

of living people

živih ljudi

and extinct humans.

i izumrlih ljudi.

But before doing that,

Ali prije no što to učinimo,

I just briefly want to remind you about what you already know:

ukratko vas želim podsjetiti o onome što već znate:

that our genomes, our genetic material,

da su naši genomi, naš genetički materijal,

are stored in almost all cells in our bodies in chromosomes

pohranjeni u gotovo svim stanicama našeg tijela u kromosomima

in the form of DNA,

u DNK formi,

which is this famous double-helical molecule.

što je ova poznata molekula dvostruke zavojnice.

And the genetic information

I genetski materijal

is contained in the form of a sequence

je sadržan u obliku niza

of four bases

od četiri baze

abbreviated with the letters A, T, C and G.

skraćene slovima A, T, C i G.

And the information is there twice --

I informacija je tu dvostruka --

one on each strand --

jedna na svakoj strani --

which is important,

što je važno

because when new cells are formed, these strands come apart,

zato što kada se stvore nove stanice, te strane se razdvoje,

new strands are synthesized with the old ones as templates

nove strane se sintetiziraju sa starima kao predložak

in an almost perfect process.

u gotovo savršenom procesu.

But nothing, of course, in nature

Ali, naravno, u prirodi ništa nije

is totally perfect,

potpuno savršeno

so sometimes an error is made

pa se ponekad potkrade greška

and a wrong letter is built in.

i ugradi se krivo slovo.

And we can then see the result

I tada možemo vidjeti rezultat

of such mutations

takvih mutacija

when we compare DNA sequences

kada usporedimo DNK niz

among us here in the room, for example.

među nama u ovoj sobi na primjer.

If we compare my genome to the genome of you,

Ako usporedim svoj genom s vašim genomom,

approximately every 1,200, 1,300 letters

otprilike svakih 1.200 – 1.300 slova

will differ between us.

će biti različito među nama.

And these mutations accumulate

I te mutacije se gomilaju

approximately as a function of time.

otprilike kao funkcija vremena.

So if we add in a chimpanzee here, we will see more differences.

Ako ovdje dodamo i čimpanzu, vidjet ćemo još više različitosti.

Approximately one letter in a hundred

Otprilike jedno slovo na njih sto

will differ from a chimpanzee.

će se razlikovati od čimpanze.

And if you're then interested in the history

I onda, ako ste zainteresirani za povijest

of a piece of DNA, or the whole genome,

komadića DNK, ili cijelog genoma

you can reconstruct the history of the DNA

možete rekonstruirati povijest DNK

with those differences you observe.

s onima čije razlike promatrate.

And generally we depict our ideas about this history

I općenito, naše ideje o ovoj povijesti opisujemo

in the form of trees like this.

u oblicima drveta poput ovog.

In this case, it's very simple.

U ovom slučaju, veoma jednostavno.

The two human DNA sequences

Dvije ljudske DNK sekvence

go back to a common ancestor quite recently.

se vraćaju do zajedničkog pretka relativno nedavno.

Farther back is there one shared with chimpanzees.

Još dalje je jedan kojeg dijelimo s čimpanzama.

And because these mutations

I zbog toga mutacije

happen approximately as a function of time,

se događaju otprilike kao funkcija vremena,

you can transform these differences

možete pretvoriti ove razlike

to estimates of time,

u procjenu vremena

where the two humans, typically,

gdje će dvoje ljudi, tipično,

will share a common ancestor about half a million years ago,

dijeliti zajedničkog pretka od prije pola milijuna godina

and with the chimpanzees,

i sa čimpanzama,

it will be in the order of five million years ago.

bit će na redu od prije pet milijuna godina.

So what has now happened in the last few years

Ono što se sada dogodilo je da u posljednjih nekoliko godina

is that there are account technologies around

postoje tehnologije računanja

that allow you to see many, many pieces of DNA very quickly.

koje vam dozvoljavaju da vidite mnogo, mnogo dijelova DNK i to veoma brzo.

So we can now, in a matter of hours,

Tako sad u nekoliko sati možemo

determine a whole human genome.

odrediti cijeli ljudski genom.

Each of us, of course, contains two human genomes --

Svatko od nas, naravno, sadrži dva ljudska genoma --

one from our mothers and one from our fathers.

jedan od naših majki i jedan od naših očeva.

And they are around three billion such letters long.

I dugi su otprilike tri milijarde takvih slova.

And we will find that the two genomes in me,

I otkrit ćemo da dva genoma u meni

or one genome of mine we want to use,

ili jedan genom koji želimo iskoristiti

will have about three million differences

ima oko tri milijarde razlika

in the order of that.

zbog toga.

And what you can then also begin to do

I ono što također možete početi raditi

is to say, "How are these genetic differences

je da kažete kako se ove genetičke razlike

distributed across the world?"

prikazuju diljem svijeta.

And if you do that,

I ako to učinite,

you find a certain amount of genetic variation in Africa.

pronaći ćete određenu količinu genetičkih varijacija u Africi.

And if you look outside Africa,

A ako pogledate izvan Afrike,

you actually find less genetic variation.

zapravo ćete pronaći manje genetičkih varijacija.

This is surprising, of course,

To je iznenađujuće, naravno,

because in the order of six to eight times fewer people

zbog toga što u Africi živi šest do osam puta manje ljudi

live in Africa than outside Africa.

nego van Afrike.

Yet the people inside Africa

Unatoč tome ljudi u Africi

have more genetic variation.

imaju više genetičkih varijacija.

Moreover, almost all these genetic variants

Štoviše, gotovo sve ove genetičke varijacije

we see outside Africa

koje vidimo izvan Afrike

have closely related DNA sequences

imaju veoma usko povezane DNK sekvence

that you find inside Africa.

koje ćete pronaći i u Africi.

But if you look in Africa,

Ali ako pogledate u Africi

there is a component of the genetic variation

postoji sastavni dio genetske varijacije

that has no close relatives outside.

koji nema usko povezane rođake izvan.

So a model to explain this

Dakle, model koji bi ovo objasnio

is that a part of the African variation, but not all of it,

je da su dijelovi afričkih promjena, ali ne svi,

[has] gone out and colonized the rest of the world.

otišli i kolonizirali ostatak svijeta.

And together with the methods to date these genetic differences,

I zajedno s metodama koje bi datirale ove genetske razlike,

this has led to the insight

to nas je dovelo do uvida

that modern humans --

da su se moderni ljudi --

humans that are essentially indistinguishable from you and me --

ljudi koji se ne razlikuju bitno od vas i mene --

evolved in Africa, quite recently,

razvili u Africi relativno nedavno

between 100 and 200,000 years ago.

prije 100 do 200.000 godina.

And later, between 100 and 50,000 years ago or so,

I kasnije, prije 100 i 50.000 godina,

went out of Africa

otišli iz Afrike

to colonize the rest of the world.

ne bi li kolonizirali ostatak svijeta.

So what I often like to say

Ono što često volim reći

is that, from a genomic perspective,

je da smo s genomske perspektive

we are all Africans.

svi Afrikanci.

We either live inside Africa today,

Ili danas živimo u Africi

or in quite recent exile.

ili smo relativno nedavno prognani.

Another consequence

Druga posljedica

of this recent origin of modern humans

ovog nedavnog podrijetla modernih ljudi

is that genetic variants

je da su genetičke varijante

are generally distributed widely in the world,

generalno raspodijeljene širom svijeta,

in many places,

na mnogo mjesta,

and they tend to vary as gradients,

i imaju tendenciju variranja poput gradijenata,

from a bird's-eye perspective at least.

barem iz ptičje perspektive.

And since there are many genetic variants,

I s obzirom da postoji mnogo genetskih varijanti

and they have different such gradients,

i imaju različite takve gradijente,

this means that if we determine a DNA sequence --

to znači da ako odredimo DNK sekvencu --

a genome from one individual --

genom iz jedne individue --

we can quite accurately estimate

možemo prilično točno procijeniti

where that person comes from,

odakle ta osoba dolazi,

provided that its parents or grandparents

pod pretpostavkom da mu se roditelji ili bake i djedovi

haven't moved around too much.

nisu previše selili.

But does this then mean,

Ali znači li to,

as many people tend to think,

kao što mnogi ljudi misle,

that there are huge genetic differences between groups of people --

da postoje velike genetičke razlike među grupama ljudi --

on different continents, for example?

na različitim kontinentima na primjer?

Well we can begin to ask those questions also.

Pa, možemo također postaviti i ta pitanja.

There is, for example, a project that's underway

Na primjer, postoji projekt koji pokušava

to sequence a thousand individuals --

sekvencirati tisuće jedinki --

their genomes -- from different parts of the world.

njihovih genoma -- iz raznih dijelova svijeta.

They've sequenced 185 Africans

Poredali su 185 Afrikanaca

from two populations in Africa.

iz dvije populacije u Africi.

[They've] sequenced approximately equally [as] many people

Poredak je otprilike jednak broju ljudi

in Europe and in China.

u Europi i Kini.

And we can begin to say how much variance do we find,

I počinjemo govoriti o tome koliko varijacija nalazimo,

how many letters that vary

koliko slova koje variraju

in at least one of those individual sequences.

u najmanje jednom od tih individualnih sekvenca.

And it's a lot: 38 million variable positions.

I mnogo ih je: 38 milijuna promjenjivih pozicija.

But we can then ask: Are there any absolute differences

Ali možemo upitati: Postoji li koja potpuna razlika

between Africans and non-Africans?

među Afrikancima i ne-Afrikancima?

Perhaps the biggest difference

Možda najveća razlika

most of us would imagine existed.

koju bi većina od nas uopće zamislila da postoji.

And with absolute difference --

A s potpunom razlikom --

and I mean a difference

i pritom mislim na razliku

where people inside Africa at a certain position,

gdje ljudi unutar Afrike na određenom mjestu,

where all individuals -- 100 percent -- have one letter,

gdje sve jedinke -- 100 posto -- imaju jedno slovo

and everybody outside Africa has another letter.

i svi van Afrike imaju drugo slovo.

And the answer to that, among those millions of differences,

I odgovor na to među milijunima

is that there is not a single such position.

tih razlika je da ne postoji nijedno takvo mjesto.

This may be surprising.

To može biti iznenađujuće.

Maybe a single individual is misclassified or so.

Možda je jedna jedinka previđena ili tako nešto.

So we can relax the criterion a bit

Možemo sniziti kriterije

and say: How many positions do we find

i reći: Koliko mjesta nalazimo tamo

where 95 percent of people in Africa have

gdje 95 posto ljudi u Africi ima

one variant,

jednu varijantu,

95 percent another variant,

95 posto drugu varijantu

and the number of that is 12.

i taj broj je 12.

So this is very surprising.

Dakle, to je veoma iznenađujuće.

It means that when we look at people

To znači da kada gledamo ljude

and see a person from Africa

i vidimo osobu iz Afrike

and a person from Europe or Asia,

i osobu iz Europe ili Azije,

we cannot, for a single position in the genome with 100 percent accuracy,

ne možemo ni za jedno mjesto u genomu sa stopostotnom sigurnošću

predict what the person would carry.

reći koju osoba nosi.

And only for 12 positions

A samo za 12 mjesta

can we hope to be 95 percent right.

se možemo nadati da će biti 95 posto točni.

This may be surprising,

To može biti iznenađujuće,

because we can, of course, look at these people

zato što možemo, naravno, pogledati te ljude

and quite easily say where they or their ancestors came from.

i veoma lako reći odakle im dolaze preci.

So what this means now

To sada znači

is that those traits we then look at

da ta svojstva koja pogledamo

and so readily see --

i tako spremno vidimo --

facial features, skin color, hair structure --

svojstva lica, boja kože, struktura kose --

are not determined by single genes with big effects,

nisu određena pojedinim genima s velikim efektima

but are determined by many different genetic variants

već su određena s mnogo genetičkih varijanti

that seem to vary in frequency

za koje se čini da variraju frekventno

between different parts of the world.

među različitim dijelovima svijeta.

There is another thing with those traits

Postoji još jedna stvar s tim svojstvima

that we so easily observe in each other

koja tako lako primjećujemo jedni na drugima

that I think is worthwhile to consider,

za koje smatram da su vrijedna razmatranja,

and that is that, in a very literal sense,

a to su u veoma doslovnom smislu,

they're really on the surface of our bodies.

one su zaista na površini našeg tijela.

They are what we just said --

To je ono što smo upravo rekli --

facial features, hair structure, skin color.

svojstva lica, struktura kose, boja kože.

There are also a number of features

Postoje također brojne značajke

that vary between continents like that

koje variraju među kontinentima na način

that have to do with how we metabolize food that we ingest,

da se moramo nositi s time kako metaboliziramo hranu koju jedemo

or that have to do

ili kako

with how our immune systems deal with microbes

se naš organizam bori s mikrobima

that try to invade our bodies.

koji pokušavaju napasti naše tijelo.

But so those are all parts of our bodies

Ali sve su to dijelovi našeg tijela

where we very directly interact with our environment,

s kojima veoma direktno sudjelujemo s okolinom,

in a direct confrontation, if you like.

u veoma direktnom suočavanju, ako želite.

It's easy to imagine

Lako je zamisliti

how particularly those parts of our bodies

kako su naročito ti dijelovi naših tijela

were quickly influenced by selection from the environment

brzo pali pod utjecaj selekcije iz prirode

and shifted frequencies of genes

i pomaknuli učestalost gena

that are involved in them.

koji su uključeni u njih.

But if we look on other parts of our bodies

Ali ako pogledamo druge dijelove tijela

where we don't directly interact with the environment --

s kojima nismo direktno u kontaktu s okolinom --

our kidneys, our livers, our hearts --

naše bubrege, našu jetru, naša srca --

there is no way to say,

nema načina na koji bismo rekli

by just looking at these organs,

samo gledajući te organe,

where in the world they would come from.

odakle su iz cijelog svijeta oni došli.

So there's another interesting thing

Dakle, postoji još jedna zanimljiva stvar

that comes from this realization

koja proizlazi iz spoznaje

that humans have a recent common origin in Africa,

da ljudi imaju zajedničko podrijetlo u Africi,

and that is that when those humans emerged

a kad su se ti ljudi pojavili

around 100,000 years ago or so,

prije otprilike 100.000 godina,

they were not alone on the planet.

nisu bili sami na planeti.

There were other forms of humans around,

Bilo je drugih vrsta ljudi,

most famously perhaps, Neanderthals --

možda najpoznatiji -- Neandertalci --

these robust forms of humans,

robustan oblik ljudi,

compared to the left here

s lijeve strane, u odnosu na

with a modern human skeleton on the right --

moderni ljudski kostur na desnoj strani --

that existed in Western Asia and Europe

koji su postojali u Zapadnoj Aziji i Europi

since several hundreds of thousands of years.

nekoliko stotina tisuća godina.

So an interesting question is,

Dakle, zanimljivo pitanje je,

what happened when we met?

što se dogodilo kada smo se susreli?

What happened to the Neanderthals?

Što se dogodilo s Neandertalcima?

And to begin to answer such questions,

Kako bi mogli odgovoriti na takva pitanja,

my research group -- since over 25 years now --

moja istraživačka skupina -- preko 25 godina --

works on methods to extract DNA

radi na metodama za izdvajanje DNK

from remains of Neanderthals

iz ostataka Neandertalaca

and extinct animals

i izumrlih životinja

that are tens of thousands of years old.

koje su stare desetke tisuća godina.

So this involves a lot of technical issues

Dakle, to uključuje puno tehničkih problema

in how you extract the DNA,

u tome kako izvući DNK,

how you convert it to a form you can sequence.

kako ga pretvoriti u oblik koji možete sekvencirati.

You have to work very carefully

Morate raditi vrlo pažljivo

to avoid contamination of experiments

kako bi izbjegli kontaminaciju eksperimenata

with DNA from yourself.

s vlastitom DNK.

And this then, in conjunction with these methods

A to, zahvaljujući metodama

that allow very many DNA molecules to be sequenced very rapidly,

koje omogućuju da se veliki broj molekula DNK jako brzo sekvencira,

allowed us last year

nam je omogućilo da prošle godine

to present the first version of the Neanderthal genome,

predstavimo prvu verziju genoma Neandertalca,

so that any one of you

tako da bilo tko od vas

can now look on the Internet, on the Neanderthal genome,

sada može pogledati na internetu genom Neandertalca,

or at least on the 55 percent of it

ili barem onih 55 posto

that we've been able to reconstruct so far.

što smo do sada uspjeli rekonstruirati.

And you can begin to compare it to the genomes

A možete ga početi uspoređivati s genomom

of people who live today.

ljudi koji žive danas.

And one question

I jedno pitanje

that you may then want to ask

koje si možete postaviti

is, what happened when we met?

je što se dogodilo kada smo se susreli?

Did we mix or not?

Jesmo li se pomiješali ili ne?

And the way to ask that question

A jedan od načina kako postaviti to pitanje

is to look at the Neanderthal that comes from Southern Europe

je da pogledamo Neandertalca koji dolazi iz južne Europe

and compare it to genomes

i da njegov genom usporedimo s genomom

of people who live today.

ljudi koji žive danas.

So we then look

To moramo učiniti

to do this with pairs of individuals,

s parovima pojedinaca,

starting with two Africans,

počevši s dva Afrikanca,

looking at the two African genomes,

gledajući dva afrička genoma

finding places where they differ from each other,

i pronalazeći mjesta na kojima se razlikuju jedan od drugog,

and in each case ask: What is a Neanderthal like?

u svakom slučaju se zapitati: Što je poput Neandertalca?

Does it match one African or the other African?

Je li sličan jednom ili drugom Afrikancu?

We would expect there to be no difference,

Mi bismo očekivali da neće biti razlike

because Neanderthals were never in Africa.

jer Neandertalci nisu nikada bili u Africi.

They should be equal, have no reason to be closer

Oni bi trebali biti jednaki, nemaju razloga biti bliži

to one African than another African.

jednom Afrikancu, a drugom ne.

And that's indeed the case.

I to je doista slučaj.

Statistically speaking, there is no difference

Statistički gledano, ne postoji razlika

in how often the Neanderthal matches one African or the other.

u tome koliko Neandertalac odgovara jednom ili drugom Afrikancu.

But this is different

Ali to je drugačije

if we now look at the European individual and an African.

ako ćemo sada gledati Europskog pojedinca i Afričkog.

Then, significantly more often,

Tako, značajno se češće,

does a Neanderthal match the European

Neandertalac podudara s Europljaninom

rather than the African.

nego s Afrikancem.

The same is true if we look at a Chinese individual

Isto vrijedi i ako ćemo gledati kineskog pojedinca

versus an African,

u odnosu na afričkog,

the Neanderthal will match the Chinese individual more often.

Neandertalac će odgovarati kineskom pojedincu češće.

This may also be surprising

To je također iznenađujuće

because the Neanderthals were never in China.

jer Neandertalci nisu nikada bili u Kini.

So the model we've proposed to explain this

Dakle, model koji smo predložili da ovo objasni

is that when modern humans came out of Africa

je taj kada su moderni ljudi otišli iz Afrike

sometime after 100,000 years ago,

negdje prije 100.000 godina

they met Neanderthals.

susreli su se s Neandertalcima.

Presumably, they did so first in the Middle East,

To se vjerojatno dogodilo na Bliskom istoku,

where there were Neanderthals living.

gdje su Neandertalci živjeli.

If they then mixed with each other there,

Ako su se tada međusobno pomiješali,

then those modern humans

onda su ti moderni ljudi

that became the ancestors

koji su postali preci

of everyone outside Africa

svih ljudi izvan Afrike,

carried with them this Neanderthal component in their genome

nosili u sebi neandertalsku komponentu u genomu

to the rest of the world.

i prenijeli ih ostatku svijeta.

So that today, the people living outside Africa

Tako da danas, ljudi koji žive izvan Afrike

have about two and a half percent of their DNA

imaju oko 2.5 posto svoje DNK

from Neanderthals.

koja potječe od Neandertalaca.

So having now a Neanderthal genome

Imajući neandertalski genom

on hand as a reference point

kao referentnu točku

and having the technologies

te tehnologiju

to look at ancient remains

kojom možemo gledati drevne ostatke

and extract the DNA,

i ekstraktirati DNK,

we can begin to apply them elsewhere in the world.

možemo ih početi primjenjivati u drugim dijelovima svijeta.

And the first place we've done that is in Southern Siberia

A prvo mjesto gdje smo to učinili je u južnom Sibiru

in the Altai Mountains

u planinama Altai

at a place called Denisova,

u mjestu zvanom Denisova,

a cave site in this mountain here,

špilja u planini

where archeologists in 2008

gdje su arheolozi 2008. godine

found a tiny little piece of bone --

pronašli komadić kosti --

this is a copy of it --

ovo je kopija --

that they realized came from the last phalanx

ustanovili su da pripada posljednjoj falangi

of a little finger of a pinky of a human.

malog prsta čovjeka.

And it was well enough preserved

Bila je jako dobro očuvana

so we could determine the DNA from this individual,

tako da smo mogli utvrditi DNK tog pojedinca,

even to a greater extent

čak u većoj mjeri

than for the Neanderthals actually,

nego za Neandertalce,

and start relating it to the Neanderthal genome

i početi uspoređivati s genomom Neandertalca

and to people today.

i današnjih ljudi.

And we found that this individual

Otkrili smo da ta osoba

shared a common origin for his DNA sequences

dijeli zajedničko podrijetlo za svoj slijed DNK

with Neanderthals around 640,000 years ago.

s Neandertalcima prije 640.000 godina.

And further back, 800,000 years ago

I dalje, 800.000 godina prije

is there a common origin

postoji zajedničko podrijetlo

with present day humans.

s današnjim ljudima.

So this individual comes from a population

Dakle, ovaj pojedinac dolazi iz populacije

that shares an origin with Neanderthals,

koja dijeli podrijetlo s Neandertalcima,

but far back and then have a long independent history.

ali dalje u prošlosti imaju dugu povijest neovisnosti.

We call this group of humans,

Ovu skupinu ljudi nazivamo,

that we then described for the first time

koje smo prvi put opisali,

from this tiny, tiny little piece of bone,

zahvaljujući malom komadiću kosti,

the Denisovans,

Denisovanci,

after this place where they were first described.

po mjestu gdje su prvi put opisani.

So we can then ask for Denisovans

Tako za njih možemo postaviti

the same things as for the Neanderthals:

isto pitanje kao i za Neandertalce:

Did they mix with ancestors of present day people?

Jesu li se miješali s precima današnjih ljudi?

If we ask that question,

Ako postavimo to pitanje,

and compare the Denisovan genome

i usporedimo Denisovanski genom

to people around the world,

s genomom ljudi diljem svijeta,

we surprisingly find

iznenađujuće,

no evidence of Denisovan DNA

ne možemo pronaći nikakav dokaz o Denisovanskom DNK

in any people living even close to Siberia today.

kod ljudi koji žive ni blizu Sibira.

But we do find it in Papua New Guinea

Ali smo ga pronašli u Papui Novoj Gvineji

and in other islands in Melanesia and the Pacific.

i na drugim otocima u Melaneziji te u Pacifiku.

So this presumably means

Dakle, to vjerojatno znači

that these Denisovans had been more widespread in the past,

da su bili znatno prošireniji u prošlosti

since we don't think that the ancestors of Melanesians

jer ne smatramo da su preci Malezijanaca

were ever in Siberia.

bili u Sibiru.

So from studying

Dakle, iz proučavanja

these genomes of extinct humans,

genoma izumrlih ljudi,

we're beginning to arrive at a picture of what the world looked like

počinjemo si predočavati kako je svijet izgledao

when modern humans started coming out of Africa.

u doba kada su moderni ljudi počeli dolaziti iz Afrike.

In the West, there were Neanderthals;

Na zapadu su bili Neandertalci,

in the East, there were Denisovans --

na istoku su bili Denisovanci --

maybe other forms of humans too

možda i druge vrste ljudi

that we've not yet described.

koje još nismo opisali.

We don't know quite where the borders between these people were,

Ne znamo gdje su bile granice između tih ljudi,

but we know that in Southern Siberia,

ali znamo da je u južnom Sibiru,

there were both Neanderthals and Denisovans

bilo je i Neandertalaca i Denisovanaca

at least at some time in the past.

barem na neko vrijeme u prošlosti.

Then modern humans emerged somewhere in Africa,

Zatim, moderni ljudi se pojavljuju u Africi,

came out of Africa, presumably in the Middle East.

dolaze iz Afrike, vjerojatno na Bliski istok.

They meet Neanderthals, mix with them,

Upoznaju Neandertalce, miješaju se s njima,

continue to spread over the world,

i nastavljaju se širiti diljem svijeta,

and somewhere in Southeast Asia,

a negdje u jugoistočnoj Aziji,

they meet Denisovans and mix with them

susreću Denisovance te se miješaju s njima

and continue on out into the Pacific.

i nastavljaju se širiti po Tihom oceanu.

And then these earlier forms of humans disappear,

A onda ti raniji oblici ljudi nestaju,

but they live on a little bit today

ali pomalo nastavljaju živjeti

in some of us --

u nekima od nas --

in that people outside of Africa have two and a half percent of their DNA

ljudi izvan Afrike imaju dva i pol posto

from Neanderthals,

neandertalske DNK,

and people in Melanesia

a ljudi u Melaneziji

actually have an additional five percent approximately

imaju dodatnih otprilike pet posto

from the Denisovans.

od Denisovanaca.

Does this then mean that there is after all

Znači li to onda da postoji

some absolute difference

apsolutna razlika

between people outside Africa and inside Africa

između ljudi izvan i unutar Afrike

in that people outside Africa

i da ljudi izvan Afrike

have this old component in their genome

imaju ove stare komponente u svom genomu

from these extinct forms of humans,

od ovih izumrlih oblika ljudi,

whereas Africans do not?

a afrikanci ne?

Well I don't think that is the case.

Pa, ja ne mislim da je to slučaj.

Presumably, modern humans

Vjerojatno je da su se moderni ljudi

emerged somewhere in Africa.

pojavili negdje u Africi.

They spread across Africa also, of course,

Oni su proširili diljem Afrike i, naravno,

and there were older, earlier forms of humans there.

tamo je bilo starijih, ranijih oblika ljudi.

And since we mixed elsewhere,

A budući da smo se miješali i drugdje,

I'm pretty sure that one day,

poprilično sam siguran da će se jednoga dana,

when we will perhaps have a genome

kada ćemo možda imati genom tih,

of also these earlier forms in Africa,

ranijih oblika ljudi u Africi,

we will find that they have also mixed

saznati da su se i oni međusobno pomiješali

with early modern humans in Africa.

s precima modernih ljudi ondje.

So to sum up,

Da zaključimo,

what have we learned from studying genomes

što smo naučili iz proučavanja genoma

of present day humans

današnjeg čovjeka

and extinct humans?

i izumrlih ljudi?

We learn perhaps many things,

Mi možda učimo mnogo stvari,

but one thing that I find sort of important to mention

ali postoji jedna stvar koju je važno napomenuti,

is that I think the lesson is that we have always mixed.

a to je pouka da smo se uvijek miješali.

We mixed with these earlier forms of humans,

Miješali smo se s ranijim oblicima ljudi,

wherever we met them,

gdjegod smo ih susreli,

and we mixed with each other ever since.

i miješamo se međusobno od tada.

Thank you for your attention.

Hvala vam na pozornosti.

(Applause)

(Pljesak)