TEDGlobal 2011
Svante Pääbo: DNA clues to our inner neanderthal
Svante Paabo: DNK tragovi do našeg unutarnjeg neandertalca
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Objavom rezultata goleme, svjetske studije, genetičar Svante Paabo pokazuje DNK dokaz da su se rani ljudi parili s neandertalcima nakon što smo se preselili u Afriku. (Da, mnogi od nas u sebi imaju neandertalski DNK.) Također pokazuje kako je sićušna kost iz malog prsta dovoljna da bi se identificirala cijela nova ljudska vrsta.
Svante Pääbo - Geneticist
Svante Pääbo explores human genetic evolution by analyzing DNA extracted from ancient sources, including mummies, an Ice Age hunter and the bone fragments of Neanderthals. Full bio
Svante Pääbo explores human genetic evolution by analyzing DNA extracted from ancient sources, including mummies, an Ice Age hunter and the bone fragments of Neanderthals. Full bio
Double-click the English transcript below to play the video.
00:15
What I want to talk to you about
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Ono o čemu vam želim govoriti
00:18
is what we can learn from studying the genomes
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je što možemo naučiti iz proučavanja genoma
00:20
of living people
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živih ljudi
00:22
and extinct humans.
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i izumrlih ljudi.
00:24
But before doing that,
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Ali prije no što to učinimo,
00:26
I just briefly want to remind you about what you already know:
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ukratko vas želim podsjetiti o onome što već znate:
00:29
that our genomes, our genetic material,
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da su naši genomi, naš genetički materijal,
00:31
are stored in almost all cells in our bodies in chromosomes
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pohranjeni u gotovo svim stanicama našeg tijela u kromosomima
00:34
in the form of DNA,
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u DNK formi,
00:36
which is this famous double-helical molecule.
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što je ova poznata molekula dvostruke zavojnice.
00:39
And the genetic information
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I genetski materijal
00:41
is contained in the form of a sequence
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je sadržan u obliku niza
00:43
of four bases
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od četiri baze
00:45
abbreviated with the letters A, T, C and G.
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skraćene slovima A, T, C i G.
00:48
And the information is there twice --
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I informacija je tu dvostruka --
00:50
one on each strand --
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jedna na svakoj strani --
00:52
which is important,
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što je važno
00:54
because when new cells are formed, these strands come apart,
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zato što kada se stvore nove stanice, te strane se razdvoje,
00:56
new strands are synthesized with the old ones as templates
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nove strane se sintetiziraju sa starima kao predložak
00:59
in an almost perfect process.
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u gotovo savršenom procesu.
01:02
But nothing, of course, in nature
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Ali, naravno, u prirodi ništa nije
01:04
is totally perfect,
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potpuno savršeno
01:06
so sometimes an error is made
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pa se ponekad potkrade greška
01:08
and a wrong letter is built in.
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i ugradi se krivo slovo.
01:11
And we can then see the result
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I tada možemo vidjeti rezultat
01:13
of such mutations
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takvih mutacija
01:15
when we compare DNA sequences
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kada usporedimo DNK niz
01:17
among us here in the room, for example.
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među nama u ovoj sobi na primjer.
01:20
If we compare my genome to the genome of you,
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Ako usporedim svoj genom s vašim genomom,
01:23
approximately every 1,200, 1,300 letters
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otprilike svakih 1.200 – 1.300 slova
01:27
will differ between us.
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će biti različito među nama.
01:29
And these mutations accumulate
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I te mutacije se gomilaju
01:31
approximately as a function of time.
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otprilike kao funkcija vremena.
01:34
So if we add in a chimpanzee here, we will see more differences.
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Ako ovdje dodamo i čimpanzu, vidjet ćemo još više različitosti.
01:37
Approximately one letter in a hundred
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Otprilike jedno slovo na njih sto
01:40
will differ from a chimpanzee.
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će se razlikovati od čimpanze.
01:42
And if you're then interested in the history
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I onda, ako ste zainteresirani za povijest
01:44
of a piece of DNA, or the whole genome,
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komadića DNK, ili cijelog genoma
01:46
you can reconstruct the history of the DNA
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možete rekonstruirati povijest DNK
01:49
with those differences you observe.
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s onima čije razlike promatrate.
01:51
And generally we depict our ideas about this history
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I općenito, naše ideje o ovoj povijesti opisujemo
01:55
in the form of trees like this.
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u oblicima drveta poput ovog.
01:57
In this case, it's very simple.
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U ovom slučaju, veoma jednostavno.
01:59
The two human DNA sequences
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Dvije ljudske DNK sekvence
02:01
go back to a common ancestor quite recently.
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se vraćaju do zajedničkog pretka relativno nedavno.
02:04
Farther back is there one shared with chimpanzees.
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Još dalje je jedan kojeg dijelimo s čimpanzama.
02:08
And because these mutations
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I zbog toga mutacije
02:11
happen approximately as a function of time,
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se događaju otprilike kao funkcija vremena,
02:13
you can transform these differences
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možete pretvoriti ove razlike
02:15
to estimates of time,
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u procjenu vremena
02:17
where the two humans, typically,
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gdje će dvoje ljudi, tipično,
02:19
will share a common ancestor about half a million years ago,
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dijeliti zajedničkog pretka od prije pola milijuna godina
02:23
and with the chimpanzees,
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i sa čimpanzama,
02:25
it will be in the order of five million years ago.
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bit će na redu od prije pet milijuna godina.
02:28
So what has now happened in the last few years
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Ono što se sada dogodilo je da u posljednjih nekoliko godina
02:30
is that there are account technologies around
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postoje tehnologije računanja
02:32
that allow you to see many, many pieces of DNA very quickly.
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koje vam dozvoljavaju da vidite mnogo, mnogo dijelova DNK i to veoma brzo.
02:36
So we can now, in a matter of hours,
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Tako sad u nekoliko sati možemo
02:38
determine a whole human genome.
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odrediti cijeli ljudski genom.
02:41
Each of us, of course, contains two human genomes --
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Svatko od nas, naravno, sadrži dva ljudska genoma --
02:44
one from our mothers and one from our fathers.
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jedan od naših majki i jedan od naših očeva.
02:47
And they are around three billion such letters long.
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I dugi su otprilike tri milijarde takvih slova.
02:51
And we will find that the two genomes in me,
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I otkrit ćemo da dva genoma u meni
02:53
or one genome of mine we want to use,
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ili jedan genom koji želimo iskoristiti
02:55
will have about three million differences
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ima oko tri milijarde razlika
02:58
in the order of that.
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zbog toga.
03:00
And what you can then also begin to do
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I ono što također možete početi raditi
03:02
is to say, "How are these genetic differences
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je da kažete kako se ove genetičke razlike
03:04
distributed across the world?"
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prikazuju diljem svijeta.
03:06
And if you do that,
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I ako to učinite,
03:08
you find a certain amount of genetic variation in Africa.
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pronaći ćete određenu količinu genetičkih varijacija u Africi.
03:12
And if you look outside Africa,
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A ako pogledate izvan Afrike,
03:15
you actually find less genetic variation.
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zapravo ćete pronaći manje genetičkih varijacija.
03:18
This is surprising, of course,
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To je iznenađujuće, naravno,
03:20
because in the order of six to eight times fewer people
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zbog toga što u Africi živi šest do osam puta manje ljudi
03:23
live in Africa than outside Africa.
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nego van Afrike.
03:26
Yet the people inside Africa
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Unatoč tome ljudi u Africi
03:29
have more genetic variation.
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imaju više genetičkih varijacija.
03:32
Moreover, almost all these genetic variants
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Štoviše, gotovo sve ove genetičke varijacije
03:34
we see outside Africa
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koje vidimo izvan Afrike
03:36
have closely related DNA sequences
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imaju veoma usko povezane DNK sekvence
03:38
that you find inside Africa.
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koje ćete pronaći i u Africi.
03:40
But if you look in Africa,
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Ali ako pogledate u Africi
03:42
there is a component of the genetic variation
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postoji sastavni dio genetske varijacije
03:45
that has no close relatives outside.
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koji nema usko povezane rođake izvan.
03:48
So a model to explain this
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Dakle, model koji bi ovo objasnio
03:51
is that a part of the African variation, but not all of it,
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je da su dijelovi afričkih promjena, ali ne svi,
03:54
[has] gone out and colonized the rest of the world.
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otišli i kolonizirali ostatak svijeta.
03:58
And together with the methods to date these genetic differences,
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I zajedno s metodama koje bi datirale ove genetske razlike,
04:02
this has led to the insight
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to nas je dovelo do uvida
04:04
that modern humans --
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da su se moderni ljudi --
04:06
humans that are essentially indistinguishable from you and me --
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ljudi koji se ne razlikuju bitno od vas i mene --
04:09
evolved in Africa, quite recently,
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razvili u Africi relativno nedavno
04:12
between 100 and 200,000 years ago.
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prije 100 do 200.000 godina.
04:16
And later, between 100 and 50,000 years ago or so,
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I kasnije, prije 100 i 50.000 godina,
04:20
went out of Africa
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otišli iz Afrike
04:22
to colonize the rest of the world.
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ne bi li kolonizirali ostatak svijeta.
04:24
So what I often like to say
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Ono što često volim reći
04:26
is that, from a genomic perspective,
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je da smo s genomske perspektive
04:28
we are all Africans.
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svi Afrikanci.
04:30
We either live inside Africa today,
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Ili danas živimo u Africi
04:33
or in quite recent exile.
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ili smo relativno nedavno prognani.
04:35
Another consequence
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Druga posljedica
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of this recent origin of modern humans
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ovog nedavnog podrijetla modernih ljudi
04:40
is that genetic variants
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je da su genetičke varijante
04:42
are generally distributed widely in the world,
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generalno raspodijeljene širom svijeta,
04:44
in many places,
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na mnogo mjesta,
04:46
and they tend to vary as gradients,
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i imaju tendenciju variranja poput gradijenata,
04:49
from a bird's-eye perspective at least.
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barem iz ptičje perspektive.
04:53
And since there are many genetic variants,
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I s obzirom da postoji mnogo genetskih varijanti
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and they have different such gradients,
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i imaju različite takve gradijente,
04:58
this means that if we determine a DNA sequence --
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to znači da ako odredimo DNK sekvencu --
05:01
a genome from one individual --
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genom iz jedne individue --
05:04
we can quite accurately estimate
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možemo prilično točno procijeniti
05:06
where that person comes from,
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odakle ta osoba dolazi,
05:08
provided that its parents or grandparents
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pod pretpostavkom da mu se roditelji ili bake i djedovi
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haven't moved around too much.
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nisu previše selili.
05:13
But does this then mean,
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Ali znači li to,
05:15
as many people tend to think,
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kao što mnogi ljudi misle,
05:17
that there are huge genetic differences between groups of people --
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da postoje velike genetičke razlike među grupama ljudi --
05:20
on different continents, for example?
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na različitim kontinentima na primjer?
05:22
Well we can begin to ask those questions also.
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Pa, možemo također postaviti i ta pitanja.
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There is, for example, a project that's underway
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Na primjer, postoji projekt koji pokušava
05:28
to sequence a thousand individuals --
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sekvencirati tisuće jedinki --
05:30
their genomes -- from different parts of the world.
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njihovih genoma -- iz raznih dijelova svijeta.
05:33
They've sequenced 185 Africans
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Poredali su 185 Afrikanaca
05:36
from two populations in Africa.
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iz dvije populacije u Africi.
05:39
[They've] sequenced approximately equally [as] many people
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Poredak je otprilike jednak broju ljudi
05:42
in Europe and in China.
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u Europi i Kini.
05:45
And we can begin to say how much variance do we find,
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I počinjemo govoriti o tome koliko varijacija nalazimo,
05:48
how many letters that vary
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koliko slova koje variraju
05:51
in at least one of those individual sequences.
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u najmanje jednom od tih individualnih sekvenca.
05:54
And it's a lot: 38 million variable positions.
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I mnogo ih je: 38 milijuna promjenjivih pozicija.
05:58
But we can then ask: Are there any absolute differences
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Ali možemo upitati: Postoji li koja potpuna razlika
06:01
between Africans and non-Africans?
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među Afrikancima i ne-Afrikancima?
06:03
Perhaps the biggest difference
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Možda najveća razlika
06:05
most of us would imagine existed.
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koju bi većina od nas uopće zamislila da postoji.
06:07
And with absolute difference --
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A s potpunom razlikom --
06:09
and I mean a difference
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i pritom mislim na razliku
06:11
where people inside Africa at a certain position,
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gdje ljudi unutar Afrike na određenom mjestu,
06:14
where all individuals -- 100 percent -- have one letter,
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gdje sve jedinke -- 100 posto -- imaju jedno slovo
06:17
and everybody outside Africa has another letter.
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i svi van Afrike imaju drugo slovo.
06:21
And the answer to that, among those millions of differences,
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I odgovor na to među milijunima
06:24
is that there is not a single such position.
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tih razlika je da ne postoji nijedno takvo mjesto.
06:29
This may be surprising.
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To može biti iznenađujuće.
06:31
Maybe a single individual is misclassified or so.
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Možda je jedna jedinka previđena ili tako nešto.
06:34
So we can relax the criterion a bit
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Možemo sniziti kriterije
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and say: How many positions do we find
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i reći: Koliko mjesta nalazimo tamo
06:38
where 95 percent of people in Africa have
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gdje 95 posto ljudi u Africi ima
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one variant,
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jednu varijantu,
06:42
95 percent another variant,
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95 posto drugu varijantu
06:44
and the number of that is 12.
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i taj broj je 12.
06:46
So this is very surprising.
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Dakle, to je veoma iznenađujuće.
06:48
It means that when we look at people
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To znači da kada gledamo ljude
06:50
and see a person from Africa
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i vidimo osobu iz Afrike
06:53
and a person from Europe or Asia,
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i osobu iz Europe ili Azije,
06:56
we cannot, for a single position in the genome with 100 percent accuracy,
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ne možemo ni za jedno mjesto u genomu sa stopostotnom sigurnošću
07:00
predict what the person would carry.
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reći koju osoba nosi.
07:02
And only for 12 positions
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A samo za 12 mjesta
07:04
can we hope to be 95 percent right.
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se možemo nadati da će biti 95 posto točni.
07:08
This may be surprising,
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To može biti iznenađujuće,
07:10
because we can, of course, look at these people
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zato što možemo, naravno, pogledati te ljude
07:12
and quite easily say where they or their ancestors came from.
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i veoma lako reći odakle im dolaze preci.
07:16
So what this means now
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To sada znači
07:18
is that those traits we then look at
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da ta svojstva koja pogledamo
07:20
and so readily see --
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i tako spremno vidimo --
07:22
facial features, skin color, hair structure --
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svojstva lica, boja kože, struktura kose --
07:25
are not determined by single genes with big effects,
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nisu određena pojedinim genima s velikim efektima
07:29
but are determined by many different genetic variants
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već su određena s mnogo genetičkih varijanti
07:32
that seem to vary in frequency
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za koje se čini da variraju frekventno
07:34
between different parts of the world.
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među različitim dijelovima svijeta.
07:36
There is another thing with those traits
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Postoji još jedna stvar s tim svojstvima
07:39
that we so easily observe in each other
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koja tako lako primjećujemo jedni na drugima
07:42
that I think is worthwhile to consider,
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za koje smatram da su vrijedna razmatranja,
07:44
and that is that, in a very literal sense,
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a to su u veoma doslovnom smislu,
07:47
they're really on the surface of our bodies.
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one su zaista na površini našeg tijela.
07:50
They are what we just said --
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To je ono što smo upravo rekli --
07:52
facial features, hair structure, skin color.
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svojstva lica, struktura kose, boja kože.
07:55
There are also a number of features
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Postoje također brojne značajke
07:57
that vary between continents like that
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koje variraju među kontinentima na način
07:59
that have to do with how we metabolize food that we ingest,
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da se moramo nositi s time kako metaboliziramo hranu koju jedemo
08:03
or that have to do
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ili kako
08:05
with how our immune systems deal with microbes
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se naš organizam bori s mikrobima
08:08
that try to invade our bodies.
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koji pokušavaju napasti naše tijelo.
08:10
But so those are all parts of our bodies
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Ali sve su to dijelovi našeg tijela
08:12
where we very directly interact with our environment,
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s kojima veoma direktno sudjelujemo s okolinom,
08:15
in a direct confrontation, if you like.
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u veoma direktnom suočavanju, ako želite.
08:19
It's easy to imagine
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Lako je zamisliti
08:21
how particularly those parts of our bodies
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kako su naročito ti dijelovi naših tijela
08:23
were quickly influenced by selection from the environment
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brzo pali pod utjecaj selekcije iz prirode
08:26
and shifted frequencies of genes
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i pomaknuli učestalost gena
08:28
that are involved in them.
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koji su uključeni u njih.
08:30
But if we look on other parts of our bodies
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Ali ako pogledamo druge dijelove tijela
08:33
where we don't directly interact with the environment --
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s kojima nismo direktno u kontaktu s okolinom --
08:35
our kidneys, our livers, our hearts --
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naše bubrege, našu jetru, naša srca --
08:38
there is no way to say,
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nema načina na koji bismo rekli
08:40
by just looking at these organs,
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samo gledajući te organe,
08:42
where in the world they would come from.
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odakle su iz cijelog svijeta oni došli.
08:46
So there's another interesting thing
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Dakle, postoji još jedna zanimljiva stvar
08:48
that comes from this realization
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koja proizlazi iz spoznaje
08:51
that humans have a recent common origin in Africa,
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da ljudi imaju zajedničko podrijetlo u Africi,
08:55
and that is that when those humans emerged
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a kad su se ti ljudi pojavili
08:58
around 100,000 years ago or so,
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prije otprilike 100.000 godina,
09:00
they were not alone on the planet.
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nisu bili sami na planeti.
09:02
There were other forms of humans around,
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Bilo je drugih vrsta ljudi,
09:05
most famously perhaps, Neanderthals --
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možda najpoznatiji -- Neandertalci --
09:08
these robust forms of humans,
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robustan oblik ljudi,
09:10
compared to the left here
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s lijeve strane, u odnosu na
09:12
with a modern human skeleton on the right --
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moderni ljudski kostur na desnoj strani --
09:16
that existed in Western Asia and Europe
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koji su postojali u Zapadnoj Aziji i Europi
09:19
since several hundreds of thousands of years.
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nekoliko stotina tisuća godina.
09:21
So an interesting question is,
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Dakle, zanimljivo pitanje je,
09:23
what happened when we met?
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što se dogodilo kada smo se susreli?
09:25
What happened to the Neanderthals?
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Što se dogodilo s Neandertalcima?
09:27
And to begin to answer such questions,
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Kako bi mogli odgovoriti na takva pitanja,
09:29
my research group -- since over 25 years now --
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moja istraživačka skupina -- preko 25 godina --
09:33
works on methods to extract DNA
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radi na metodama za izdvajanje DNK
09:35
from remains of Neanderthals
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iz ostataka Neandertalaca
09:37
and extinct animals
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i izumrlih životinja
09:39
that are tens of thousands of years old.
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koje su stare desetke tisuća godina.
09:42
So this involves a lot of technical issues
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Dakle, to uključuje puno tehničkih problema
09:45
in how you extract the DNA,
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u tome kako izvući DNK,
09:47
how you convert it to a form you can sequence.
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kako ga pretvoriti u oblik koji možete sekvencirati.
09:50
You have to work very carefully
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Morate raditi vrlo pažljivo
09:52
to avoid contamination of experiments
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kako bi izbjegli kontaminaciju eksperimenata
09:55
with DNA from yourself.
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s vlastitom DNK.
09:58
And this then, in conjunction with these methods
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A to, zahvaljujući metodama
10:01
that allow very many DNA molecules to be sequenced very rapidly,
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koje omogućuju da se veliki broj molekula DNK jako brzo sekvencira,
10:05
allowed us last year
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nam je omogućilo da prošle godine
10:07
to present the first version of the Neanderthal genome,
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predstavimo prvu verziju genoma Neandertalca,
10:10
so that any one of you
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tako da bilo tko od vas
10:12
can now look on the Internet, on the Neanderthal genome,
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sada može pogledati na internetu genom Neandertalca,
10:14
or at least on the 55 percent of it
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ili barem onih 55 posto
10:17
that we've been able to reconstruct so far.
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što smo do sada uspjeli rekonstruirati.
10:20
And you can begin to compare it to the genomes
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A možete ga početi uspoređivati s genomom
10:22
of people who live today.
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ljudi koji žive danas.
10:25
And one question
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I jedno pitanje
10:27
that you may then want to ask
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koje si možete postaviti
10:29
is, what happened when we met?
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je što se dogodilo kada smo se susreli?
10:31
Did we mix or not?
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Jesmo li se pomiješali ili ne?
10:33
And the way to ask that question
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A jedan od načina kako postaviti to pitanje
10:35
is to look at the Neanderthal that comes from Southern Europe
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je da pogledamo Neandertalca koji dolazi iz južne Europe
10:38
and compare it to genomes
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i da njegov genom usporedimo s genomom
10:40
of people who live today.
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ljudi koji žive danas.
10:42
So we then look
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To moramo učiniti
10:44
to do this with pairs of individuals,
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s parovima pojedinaca,
10:46
starting with two Africans,
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počevši s dva Afrikanca,
10:48
looking at the two African genomes,
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gledajući dva afrička genoma
10:50
finding places where they differ from each other,
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i pronalazeći mjesta na kojima se razlikuju jedan od drugog,
10:53
and in each case ask: What is a Neanderthal like?
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u svakom slučaju se zapitati: Što je poput Neandertalca?
10:56
Does it match one African or the other African?
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Je li sličan jednom ili drugom Afrikancu?
10:59
We would expect there to be no difference,
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Mi bismo očekivali da neće biti razlike
11:02
because Neanderthals were never in Africa.
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jer Neandertalci nisu nikada bili u Africi.
11:04
They should be equal, have no reason to be closer
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Oni bi trebali biti jednaki, nemaju razloga biti bliži
11:07
to one African than another African.
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jednom Afrikancu, a drugom ne.
11:10
And that's indeed the case.
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I to je doista slučaj.
11:12
Statistically speaking, there is no difference
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Statistički gledano, ne postoji razlika
11:14
in how often the Neanderthal matches one African or the other.
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u tome koliko Neandertalac odgovara jednom ili drugom Afrikancu.
11:18
But this is different
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Ali to je drugačije
11:20
if we now look at the European individual and an African.
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ako ćemo sada gledati Europskog pojedinca i Afričkog.
11:24
Then, significantly more often,
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Tako, značajno se češće,
11:27
does a Neanderthal match the European
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Neandertalac podudara s Europljaninom
11:29
rather than the African.
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nego s Afrikancem.
11:31
The same is true if we look at a Chinese individual
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Isto vrijedi i ako ćemo gledati kineskog pojedinca
11:34
versus an African,
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u odnosu na afričkog,
11:36
the Neanderthal will match the Chinese individual more often.
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Neandertalac će odgovarati kineskom pojedincu češće.
11:40
This may also be surprising
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To je također iznenađujuće
11:42
because the Neanderthals were never in China.
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jer Neandertalci nisu nikada bili u Kini.
11:44
So the model we've proposed to explain this
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Dakle, model koji smo predložili da ovo objasni
11:48
is that when modern humans came out of Africa
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je taj kada su moderni ljudi otišli iz Afrike
11:50
sometime after 100,000 years ago,
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negdje prije 100.000 godina
11:53
they met Neanderthals.
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susreli su se s Neandertalcima.
11:55
Presumably, they did so first in the Middle East,
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To se vjerojatno dogodilo na Bliskom istoku,
11:58
where there were Neanderthals living.
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gdje su Neandertalci živjeli.
12:00
If they then mixed with each other there,
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Ako su se tada međusobno pomiješali,
12:02
then those modern humans
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onda su ti moderni ljudi
12:04
that became the ancestors
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koji su postali preci
12:06
of everyone outside Africa
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svih ljudi izvan Afrike,
12:08
carried with them this Neanderthal component in their genome
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nosili u sebi neandertalsku komponentu u genomu
12:11
to the rest of the world.
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i prenijeli ih ostatku svijeta.
12:13
So that today, the people living outside Africa
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Tako da danas, ljudi koji žive izvan Afrike
12:16
have about two and a half percent of their DNA
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imaju oko 2.5 posto svoje DNK
12:19
from Neanderthals.
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koja potječe od Neandertalaca.
12:21
So having now a Neanderthal genome
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Imajući neandertalski genom
12:24
on hand as a reference point
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kao referentnu točku
12:26
and having the technologies
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te tehnologiju
12:28
to look at ancient remains
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kojom možemo gledati drevne ostatke
12:30
and extract the DNA,
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i ekstraktirati DNK,
12:32
we can begin to apply them elsewhere in the world.
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možemo ih početi primjenjivati u drugim dijelovima svijeta.
12:36
And the first place we've done that is in Southern Siberia
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A prvo mjesto gdje smo to učinili je u južnom Sibiru
12:39
in the Altai Mountains
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u planinama Altai
12:41
at a place called Denisova,
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u mjestu zvanom Denisova,
12:43
a cave site in this mountain here,
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špilja u planini
12:45
where archeologists in 2008
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gdje su arheolozi 2008. godine
12:48
found a tiny little piece of bone --
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pronašli komadić kosti --
12:50
this is a copy of it --
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ovo je kopija --
12:52
that they realized came from the last phalanx
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ustanovili su da pripada posljednjoj falangi
12:56
of a little finger of a pinky of a human.
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malog prsta čovjeka.
12:59
And it was well enough preserved
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Bila je jako dobro očuvana
13:01
so we could determine the DNA from this individual,
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tako da smo mogli utvrditi DNK tog pojedinca,
13:04
even to a greater extent
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čak u većoj mjeri
13:06
than for the Neanderthals actually,
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nego za Neandertalce,
13:08
and start relating it to the Neanderthal genome
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i početi uspoređivati s genomom Neandertalca
13:10
and to people today.
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i današnjih ljudi.
13:13
And we found that this individual
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Otkrili smo da ta osoba
13:15
shared a common origin for his DNA sequences
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dijeli zajedničko podrijetlo za svoj slijed DNK
13:18
with Neanderthals around 640,000 years ago.
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s Neandertalcima prije 640.000 godina.
13:22
And further back, 800,000 years ago
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I dalje, 800.000 godina prije
13:25
is there a common origin
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postoji zajedničko podrijetlo
13:27
with present day humans.
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s današnjim ljudima.
13:29
So this individual comes from a population
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Dakle, ovaj pojedinac dolazi iz populacije
13:31
that shares an origin with Neanderthals,
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koja dijeli podrijetlo s Neandertalcima,
13:34
but far back and then have a long independent history.
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ali dalje u prošlosti imaju dugu povijest neovisnosti.
13:37
We call this group of humans,
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Ovu skupinu ljudi nazivamo,
13:39
that we then described for the first time
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koje smo prvi put opisali,
13:41
from this tiny, tiny little piece of bone,
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zahvaljujući malom komadiću kosti,
13:43
the Denisovans,
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Denisovanci,
13:45
after this place where they were first described.
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po mjestu gdje su prvi put opisani.
13:48
So we can then ask for Denisovans
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Tako za njih možemo postaviti
13:51
the same things as for the Neanderthals:
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isto pitanje kao i za Neandertalce:
13:53
Did they mix with ancestors of present day people?
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Jesu li se miješali s precima današnjih ljudi?
13:57
If we ask that question,
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Ako postavimo to pitanje,
13:59
and compare the Denisovan genome
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i usporedimo Denisovanski genom
14:01
to people around the world,
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s genomom ljudi diljem svijeta,
14:03
we surprisingly find
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iznenađujuće,
14:05
no evidence of Denisovan DNA
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ne možemo pronaći nikakav dokaz o Denisovanskom DNK
14:07
in any people living even close to Siberia today.
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kod ljudi koji žive ni blizu Sibira.
14:12
But we do find it in Papua New Guinea
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Ali smo ga pronašli u Papui Novoj Gvineji
14:14
and in other islands in Melanesia and the Pacific.
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i na drugim otocima u Melaneziji te u Pacifiku.
14:18
So this presumably means
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Dakle, to vjerojatno znači
14:20
that these Denisovans had been more widespread in the past,
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da su bili znatno prošireniji u prošlosti
14:23
since we don't think that the ancestors of Melanesians
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jer ne smatramo da su preci Malezijanaca
14:26
were ever in Siberia.
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bili u Sibiru.
14:28
So from studying
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Dakle, iz proučavanja
14:30
these genomes of extinct humans,
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genoma izumrlih ljudi,
14:33
we're beginning to arrive at a picture of what the world looked like
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počinjemo si predočavati kako je svijet izgledao
14:36
when modern humans started coming out of Africa.
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u doba kada su moderni ljudi počeli dolaziti iz Afrike.
14:39
In the West, there were Neanderthals;
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Na zapadu su bili Neandertalci,
14:42
in the East, there were Denisovans --
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na istoku su bili Denisovanci --
14:44
maybe other forms of humans too
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možda i druge vrste ljudi
14:46
that we've not yet described.
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koje još nismo opisali.
14:48
We don't know quite where the borders between these people were,
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Ne znamo gdje su bile granice između tih ljudi,
14:51
but we know that in Southern Siberia,
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ali znamo da je u južnom Sibiru,
14:53
there were both Neanderthals and Denisovans
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bilo je i Neandertalaca i Denisovanaca
14:55
at least at some time in the past.
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barem na neko vrijeme u prošlosti.
14:58
Then modern humans emerged somewhere in Africa,
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Zatim, moderni ljudi se pojavljuju u Africi,
15:01
came out of Africa, presumably in the Middle East.
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dolaze iz Afrike, vjerojatno na Bliski istok.
15:04
They meet Neanderthals, mix with them,
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Upoznaju Neandertalce, miješaju se s njima,
15:07
continue to spread over the world,
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i nastavljaju se širiti diljem svijeta,
15:10
and somewhere in Southeast Asia,
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a negdje u jugoistočnoj Aziji,
15:13
they meet Denisovans and mix with them
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susreću Denisovance te se miješaju s njima
15:15
and continue on out into the Pacific.
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i nastavljaju se širiti po Tihom oceanu.
15:18
And then these earlier forms of humans disappear,
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A onda ti raniji oblici ljudi nestaju,
15:21
but they live on a little bit today
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ali pomalo nastavljaju živjeti
15:24
in some of us --
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u nekima od nas --
15:26
in that people outside of Africa have two and a half percent of their DNA
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ljudi izvan Afrike imaju dva i pol posto
15:29
from Neanderthals,
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neandertalske DNK,
15:31
and people in Melanesia
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a ljudi u Melaneziji
15:33
actually have an additional five percent approximately
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imaju dodatnih otprilike pet posto
15:36
from the Denisovans.
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od Denisovanaca.
15:39
Does this then mean that there is after all
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Znači li to onda da postoji
15:41
some absolute difference
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apsolutna razlika
15:43
between people outside Africa and inside Africa
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između ljudi izvan i unutar Afrike
15:46
in that people outside Africa
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i da ljudi izvan Afrike
15:48
have this old component in their genome
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imaju ove stare komponente u svom genomu
15:50
from these extinct forms of humans,
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od ovih izumrlih oblika ljudi,
15:52
whereas Africans do not?
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a afrikanci ne?
15:54
Well I don't think that is the case.
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Pa, ja ne mislim da je to slučaj.
15:57
Presumably, modern humans
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Vjerojatno je da su se moderni ljudi
15:59
emerged somewhere in Africa.
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pojavili negdje u Africi.
16:01
They spread across Africa also, of course,
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Oni su proširili diljem Afrike i, naravno,
16:04
and there were older, earlier forms of humans there.
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tamo je bilo starijih, ranijih oblika ljudi.
16:07
And since we mixed elsewhere,
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A budući da smo se miješali i drugdje,
16:09
I'm pretty sure that one day,
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poprilično sam siguran da će se jednoga dana,
16:11
when we will perhaps have a genome
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kada ćemo možda imati genom tih,
16:13
of also these earlier forms in Africa,
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ranijih oblika ljudi u Africi,
16:15
we will find that they have also mixed
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saznati da su se i oni međusobno pomiješali
16:17
with early modern humans in Africa.
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s precima modernih ljudi ondje.
16:21
So to sum up,
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Da zaključimo,
16:23
what have we learned from studying genomes
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što smo naučili iz proučavanja genoma
16:25
of present day humans
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današnjeg čovjeka
16:27
and extinct humans?
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i izumrlih ljudi?
16:29
We learn perhaps many things,
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Mi možda učimo mnogo stvari,
16:31
but one thing that I find sort of important to mention
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ali postoji jedna stvar koju je važno napomenuti,
16:36
is that I think the lesson is that we have always mixed.
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a to je pouka da smo se uvijek miješali.
16:39
We mixed with these earlier forms of humans,
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Miješali smo se s ranijim oblicima ljudi,
16:41
wherever we met them,
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gdjegod smo ih susreli,
16:43
and we mixed with each other ever since.
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i miješamo se međusobno od tada.
16:47
Thank you for your attention.
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Hvala vam na pozornosti.
16:49
(Applause)
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(Pljesak)
ABOUT THE SPEAKER
Svante Pääbo - GeneticistSvante Pääbo explores human genetic evolution by analyzing DNA extracted from ancient sources, including mummies, an Ice Age hunter and the bone fragments of Neanderthals.
Why you should listen
Svante Pääbo's research on the DNA of human and nonhuman primates has exposed the key genetic changes that transformed our grunting ape-like ancestors into the charming latte-sipping humans we are today. As a director at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, Pääbo and his team developed a technique of isolating and sequencing the DNA of creatures long extinct, using a variety of fragile, ancient source material from Homo sapiens and other human species.
His work shows that all humans trace their ancestry to a small population of Africans who later spread out across the world. We’ve also learned that Neanderthals, the short stocky hunters who disappeared 30,000 years ago, mated with the more modern human species and left their imprint deep within our genome. In 2007, Time named the Swedish biologist one of the 100 Most Influential People in the World for his work.
He says: "Neanderthals are not totally extinct. In some of us they live on, a little bit."
Svante Pääbo | Speaker | TED.com