TEDGlobal 2011
Svante Pääbo: DNA clues to our inner neanderthal
Svante Pabo (Svante Paabo): DNK tragovi do našeg unutrašnjeg neandertalca
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Objavljivanjem rezultata velikog istraživanja sprovedenog širom sveta, genetičar Svante Pabo (Svante Paabo) pokazuje DNK dokaz da su se rani ljudi parili sa Neandertalcima pošto smo se iselili iz Afrike. (Da, mnogi od nas imaju neandertalsku DNK.) Pabo takođe pokazuje kako je sićušna kost iz malog prsta bila dovoljna da se identifikuje cela nova humanoidna 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 želim da vam govorim
00:18
is what we can learn from studying the genomes
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je ono što možemo da saznamo proučavajući genome
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, pre nego što to uradim,
00:26
I just briefly want to remind you about what you already know:
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želim samo kratko da vas podsetim na nešto 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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uskladišteni u skoro svim ćelijama naših tela u hromozomima
00:34
in the form of DNA,
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u obliku DNK,
00:36
which is this famous double-helical molecule.
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što je čuveni molekul u obliku dvostruke spirale.
00:39
And the genetic information
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I da se genetička informacija
00:41
is contained in the form of a sequence
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nalazi u obliku sekvence
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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koje se skraćeno označavaju slovima A, T, C i G.
00:48
And the information is there twice --
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I ta informacija je tu u duplikatu --
00:50
one on each strand --
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po jedna na svakom lancu DNK --
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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jer, kada se formiraju nove ćelije, ovi lanci se razdvajaju
00:56
new strands are synthesized with the old ones as templates
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novi lanci se sintetišu koristeći stare lance kao obrasce
00:59
in an almost perfect process.
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tokom jednog skoro savršenog procesa.
01:02
But nothing, of course, in nature
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Ali, naravno, ništa u prirodi
01:04
is totally perfect,
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nije potpuno savršeno,
01:06
so sometimes an error is made
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tako da se ponekad desi greška
01:08
and a wrong letter is built in.
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i ugradi se pogrešno slovo.
01:11
And we can then see the result
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I možemo videti rezultat
01:13
of such mutations
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takvih mutacija
01:15
when we compare DNA sequences
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kada uporedimo DNK sekvence
01:17
among us here in the room, for example.
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na primer između svih nas u ovoj sali.
01:20
If we compare my genome to the genome of you,
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Ako uporedimo moj genom sa 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 se razlikovati među nama.
01:29
And these mutations accumulate
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I ove mutacije se nagomilavaju
01:31
approximately as a function of time.
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može se reći da postoji vremenska zavisnost.
01:34
So if we add in a chimpanzee here, we will see more differences.
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A ako tu ubacimo šimpanzu, videćemo više razlika.
01:37
Approximately one letter in a hundred
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Otprilike jedno slovo na svakih sto
01:40
will differ from a chimpanzee.
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će se razlikovati od šimpanzinog.
01:42
And if you're then interested in the history
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I onda, ako vas interesuje istorija
01:44
of a piece of DNA, or the whole genome,
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komadića DNK ili celog genoma,
01:46
you can reconstruct the history of the DNA
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možete da rekonstruišete istoriju DNK
01:49
with those differences you observe.
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koristeći te razlike koje ste uočili.
01:51
And generally we depict our ideas about this history
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I obično predstavljamo naše ideje o toj istoriji
01:55
in the form of trees like this.
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u obliku ovakvih razgranatih dijagrama.
01:57
In this case, it's very simple.
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U ovom slučaju je vrlo jednostavno.
01:59
The two human DNA sequences
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Ove dve ljudske DNK sekvence
02:01
go back to a common ancestor quite recently.
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idu unazad do zajedničkog pretka u skorijoj prošlosti.
02:04
Farther back is there one shared with chimpanzees.
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Još više unazad je predak kojeg dele sa šimpanzama.
02:08
And because these mutations
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I budući da ove mutacije
02:11
happen approximately as a function of time,
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uglavnom imaju vremensku zavisnost,
02:13
you can transform these differences
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možete transformisati ove razlike
02:15
to estimates of time,
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u procene vremenskih perioda,
02:17
where the two humans, typically,
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pri čemu će dve ljudske vrste, tipično
02:19
will share a common ancestor about half a million years ago,
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imati zajedničkog pretka od pre oko pola miliona godina,
02:23
and with the chimpanzees,
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dok će sa šimpanzama,
02:25
it will be in the order of five million years ago.
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to biti reda veličine od pet miliona godina.
02:28
So what has now happened in the last few years
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Dakle, ono što se dešava u poslednjih nekoliko godina
02:30
is that there are account technologies around
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je da postoje tehnologije za procenu koje
02:32
that allow you to see many, many pieces of DNA very quickly.
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nam omogućavaju da, vrlo brzo vidimo mnogo, mnogo komadića DNK.
02:36
So we can now, in a matter of hours,
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Pa tako sada možemo da, za nekoliko sati,
02:38
determine a whole human genome.
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odredimo ceo ljudski genom.
02:41
Each of us, of course, contains two human genomes --
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Svako od nas, naravno, sadrži dva humana genoma --
02:44
one from our mothers and one from our fathers.
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jedan od majke i drugi od oca.
02:47
And they are around three billion such letters long.
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I njihova dužina je oko tri milijarde ovakvih slova.
02:51
And we will find that the two genomes in me,
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I otkrićemo da dva genoma u meni
02:53
or one genome of mine we want to use,
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ili jedan moj genom koji želimo da koristimo,
02:55
will have about three million differences
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ima oko tri miliona razlika
02:58
in the order of that.
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tog reda veličina.
03:00
And what you can then also begin to do
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I zatim, ono što takođe može da se radi
03:02
is to say, "How are these genetic differences
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je da se vidi kako su te genetičke razlike
03:04
distributed across the world?"
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distribuirane širom sveta.
03:06
And if you do that,
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I ako to uradite,
03:08
you find a certain amount of genetic variation in Africa.
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otkrićete određen broj genetičkih varijacija u Africi.
03:12
And if you look outside Africa,
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A ako pogledate van Afrike,
03:15
you actually find less genetic variation.
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zapravo ćete naći manje genetičkih varijacija.
03:18
This is surprising, of course,
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To je, naravno, iznenađujuće,
03:20
because in the order of six to eight times fewer people
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jer, oko šest do osam puta manje ljudi
03:23
live in Africa than outside Africa.
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živi u Africi nego van Afrike.
03:26
Yet the people inside Africa
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A ipak, 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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Štaviše, skoro sve ove genetičke varijante
03:34
we see outside Africa
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koje nalazimo van Afrike
03:36
have closely related DNA sequences
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imaju DNK sekvence koje su blisko povezane
03:38
that you find inside Africa.
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sa onima koje se nalaze u Africi.
03:40
But if you look in Africa,
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Ali, ako posmatrate unutar Afrike,
03:42
there is a component of the genetic variation
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postoji komponenta genetičke varijacije
03:45
that has no close relatives outside.
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koja nema bliske srodnike van Afrike.
03:48
So a model to explain this
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Dakle, model koji ovo objašnjava
03:51
is that a part of the African variation, but not all of it,
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je, da je jedan deo, ali ne i celokupna afrička varijacija,
03:54
[has] gone out and colonized the rest of the world.
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izašao i kolonizovao ostatak sveta.
03:58
And together with the methods to date these genetic differences,
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I zajedno sa metodama za datiranje genetičkih razlika,
04:02
this has led to the insight
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ovo je dovelo do zaključka
04:04
that modern humans --
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da su moderni ljudi --
04:06
humans that are essentially indistinguishable from you and me --
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ljudi koji se praktično ne mogu razlikovati od vas i mene --
04:09
evolved in Africa, quite recently,
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evoluirali u Africi u vrlo skoroj prošlosti
04:12
between 100 and 200,000 years ago.
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pre oko 100 i 200.000 godina.
04:16
And later, between 100 and 50,000 years ago or so,
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I kasnije su, pre oko približno 100 i 50.000 godina
04:20
went out of Africa
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izašli iz Afrike
04:22
to colonize the rest of the world.
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da kolonizuju ostatak sveta.
04:24
So what I often like to say
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Dakle, ono što ja često volim da kažem
04:26
is that, from a genomic perspective,
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je da smo, iz genomske perspektive,
04:28
we are all Africans.
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mi svi Afrikanci.
04:30
We either live inside Africa today,
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Sada, ili živimo u Africi,
04:33
or in quite recent exile.
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ili smo u egzilu koji je nedavno počeo.
04:35
Another consequence
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Još jedna posledica
04:37
of this recent origin of modern humans
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ovog ne tako davnog porekla 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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obično široko rasprostranjene širom sveta,
04:44
in many places,
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na mnogo mesta,
04:46
and they tend to vary as gradients,
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i imaju tendenciju da variraju u vidu gradijenata,
04:49
from a bird's-eye perspective at least.
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bar kad se posmatra iz ptičje perspektive.
04:53
And since there are many genetic variants,
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I budući da postoji mnogo genetičkih varijanti,
04:55
and they have different such gradients,
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i da se njihovi gradijenti razlikuju,
04:58
this means that if we determine a DNA sequence --
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sledi zaključak da, ako odredimo DNK sekvencu --
05:01
a genome from one individual --
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genom jednog pojedinca --
05:04
we can quite accurately estimate
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možemo vrlo pouzdano da procenimo
05:06
where that person comes from,
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odakle je ta osoba,
05:08
provided that its parents or grandparents
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uz uslov da se roditelji te osobe, kao i njihovi roditelji
05:10
haven't moved around too much.
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nisu suviše često selili.
05:13
But does this then mean,
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Ali, da li ovo sada znači,
05:15
as many people tend to think,
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kao što mnogo ljudi ima tendenciju da smatra,
05:17
that there are huge genetic differences between groups of people --
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da postoje ogromne genetičke razlike između grupa ljudi --
05:20
on different continents, for example?
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na primer, na različitim kontinentima?
05:22
Well we can begin to ask those questions also.
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Pa, možemo početi da postavljamo i takva pitanja.
05:25
There is, for example, a project that's underway
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Postoji, na primer, projekat koji je na putu
05:28
to sequence a thousand individuals --
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da sekvencionira hiljadu pojedinaca --
05:30
their genomes -- from different parts of the world.
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njihove genome -- iz različitih delova sveta.
05:33
They've sequenced 185 Africans
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Do sada su sekvencionirali 185 Afrikanaca
05:36
from two populations in Africa.
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iz dve populacije u Africi.
05:39
[They've] sequenced approximately equally [as] many people
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Sekvencionirali su približno isto toliko ljudi
05:42
in Europe and in China.
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u Evropi i u Kini.
05:45
And we can begin to say how much variance do we find,
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I možemo početi da govorimo koliko variranja je nađeno,
05:48
how many letters that vary
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koliko slova varira
05:51
in at least one of those individual sequences.
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u bar jednoj od tih pojedinačnih sekvenci.
05:54
And it's a lot: 38 million variable positions.
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I to je mnogo: 38 miliona varijabilnih pozicija.
05:58
But we can then ask: Are there any absolute differences
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Ali, možemo pitati: Da li postoje neke apsolutne razlike
06:01
between Africans and non-Africans?
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između Afrikanaca i ne-Afrikanaca?
06:03
Perhaps the biggest difference
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Možda i najveća razlika
06:05
most of us would imagine existed.
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koju većina nas može da zamisli zaista postoji.
06:07
And with absolute difference --
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I kad kažem "apsolutna razlika" --
06:09
and I mean a difference
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pod tim mislim razlika
06:11
where people inside Africa at a certain position,
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pri kojoj ljudi u Africi, na određenoj poziciji,
06:14
where all individuals -- 100 percent -- have one letter,
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pri kojoj svi pojedinci -- 100 procenata -- imaju jedno slovo,
06:17
and everybody outside Africa has another letter.
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a svi drugi van Afrike imaju neko drugo slovo.
06:21
And the answer to that, among those millions of differences,
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I odgovor na to je da, od svih tih miliona razlika,
06:24
is that there is not a single such position.
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nema nijedne takve pozicije.
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 jedan pojedinac pogrešno klasifikovan ili tako nešto.
06:34
So we can relax the criterion a bit
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Pa možemo da malo spustimo kriterijum
06:36
and say: How many positions do we find
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i da kažemo: Koliko pozicija možemo naći
06:38
where 95 percent of people in Africa have
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gde 95 procenata ljudi u Africi ima
06:40
one variant,
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jednu varijantu,
06:42
95 percent another variant,
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a 95 procenata drugu varijantu,
06:44
and the number of that is 12.
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i taj broj iznosi 12.
06:46
So this is very surprising.
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I to je veoma iznenađujuće.
06:48
It means that when we look at people
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To znači da, kada ispitujemo ljude
06:50
and see a person from Africa
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i uočimo osobu iz Afrike
06:53
and a person from Europe or Asia,
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i osobu iz Evrope 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 jednu poziciju u genomu sa 100-procentnom sigurnošću,
07:00
predict what the person would carry.
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predvideti šta će ta osoba nositi.
07:02
And only for 12 positions
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I samo za 12 pozicija
07:04
can we hope to be 95 percent right.
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se možemo nadati da budemo 95 procenata u pravu.
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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jer možemo, naravno, pogledati te ljude
07:12
and quite easily say where they or their ancestors came from.
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i sasvim lako reći odakle potiču oni ili njihovi preci.
07:16
So what this means now
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To, dakle, znači da
07:18
is that those traits we then look at
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te osobine koje tada posmatramo
07:20
and so readily see --
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i tako lako uočavamo --
07:22
facial features, skin color, hair structure --
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crte lica, boja kože, struktura kose --
07:25
are not determined by single genes with big effects,
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nisu određene pojedinačnim genima sa velikim efektima,
07:29
but are determined by many different genetic variants
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već ih određuje mnogo različitih genetičkih varijanti
07:32
that seem to vary in frequency
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koje izgleda imaju različitu zastupljenost
07:34
between different parts of the world.
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u različitim delovima sveta.
07:36
There is another thing with those traits
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Postoji još jedna stvar sa tim osobinama
07:39
that we so easily observe in each other
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koje tako lako primećujemo jedni na drugima
07:42
that I think is worthwhile to consider,
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koju smatram da je korisno da razmotrimo,
07:44
and that is that, in a very literal sense,
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i to je da su, u vrlo bukvalnom smislu,
07:47
they're really on the surface of our bodies.
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te osobine, u stvari, samo na površini tela.
07:50
They are what we just said --
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Te osobine su ono što smo upravo rekli --
07:52
facial features, hair structure, skin color.
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crte lica, struktura kose, boja kože,
07:55
There are also a number of features
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Postoji takođe i određen broj osobina
07:57
that vary between continents like that
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koje variraju između kontinenata i imaju veze
07:59
that have to do with how we metabolize food that we ingest,
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sa tim kako metabolišemo hranu koju unosimo,
08:03
or that have to do
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ili sa tim
08:05
with how our immune systems deal with microbes
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kako se naš imuni sistem nosi sa mikrobima
08:08
that try to invade our bodies.
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koji pokušavaju da osvoje naša tela.
08:10
But so those are all parts of our bodies
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Ali, to su sve delovi tela
08:12
where we very directly interact with our environment,
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preko kojih mi vrlo direktno interagujemo sa okruženjem,
08:15
in a direct confrontation, if you like.
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u direktnom sučeljavanju, može se reći.
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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da su posebno ti delovi naših tela
08:23
were quickly influenced by selection from the environment
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bili brzo uobličavani putem selekcije iz okruženja
08:26
and shifted frequencies of genes
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i da je to pomerilo učestalost gena
08:28
that are involved in them.
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koji su povezani sa njima.
08:30
But if we look on other parts of our bodies
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Ali, ako pogledamo druge delove tela
08:33
where we don't directly interact with the environment --
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koji nisu u direktnom kontaktu sa okruženjem --
08:35
our kidneys, our livers, our hearts --
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naši bubrezi, jetra, naše srce --
08:38
there is no way to say,
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ne postoji način da se kaže,
08:40
by just looking at these organs,
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samo gledanjem na ove organe,
08:42
where in the world they would come from.
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iz kog dela sveta potiču.
08:46
So there's another interesting thing
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Dakle, postoji druga interesantna stvar
08:48
that comes from this realization
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koja sledi iz ovog shvatanja
08:51
that humans have a recent common origin in Africa,
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da ljudi imaju nedavno zajedničko poreklo u Africi,
08:55
and that is that when those humans emerged
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a to je da, kada su se ti ljudi pojavili
08:58
around 100,000 years ago or so,
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pre oko 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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Postojale su druge forme ljudi
09:05
most famously perhaps, Neanderthals --
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najčuveniji su, verovatno, Neandertalci --
09:08
these robust forms of humans,
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te robusne forme ljudi,
09:10
compared to the left here
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ovde sa leve strane, u poređenju
09:12
with a modern human skeleton on the right --
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sa modernim ljudskim skeletom sa desne strane --
09:16
that existed in Western Asia and Europe
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koja je postojala u Zapadnoj Aziji i Evropi
09:19
since several hundreds of thousands of years.
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od pre nekoliko stotina hiljada 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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šta se desilo kada smo se sreli?
09:25
What happened to the Neanderthals?
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Šta se desilo sa Neandertalcima?
09:27
And to begin to answer such questions,
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I da bismo počeli da odgovaramo na takva pitanja,
09:29
my research group -- since over 25 years now --
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moja istraživačka grupa -- već više od 25 godina --
09:33
works on methods to extract DNA
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radi na metodama ekstrakcije 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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starih desetine hiljada godina.
09:42
So this involves a lot of technical issues
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To uključuje veliki broj tehničkih detalja
09:45
in how you extract the DNA,
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o tome kako se izoluje DNK,
09:47
how you convert it to a form you can sequence.
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kako se konvertuje u oblik koji može da se sekvencionira.
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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da biste izbegli kontaminaciju eksperimenta
09:55
with DNA from yourself.
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svojom sopstvenom DNK.
09:58
And this then, in conjunction with these methods
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I zahvaljujući ovome, zajedno sa onim metodama
10:01
that allow very many DNA molecules to be sequenced very rapidly,
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koje omogućavaju da veoma mnogo DNK molekula može vrlo brzo da se sekvencionira,
10:05
allowed us last year
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smo prošle godine
10:07
to present the first version of the Neanderthal genome,
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uspeli da pokažemo prvu verziju neandertalskog genoma,
10:10
so that any one of you
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pa tako bilo ko od vas
10:12
can now look on the Internet, on the Neanderthal genome,
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može da pogleda na Internetu i nađe neandertalski genom,
10:14
or at least on the 55 percent of it
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ili bar 55 procenata tog genoma
10:17
that we've been able to reconstruct so far.
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što smo do sada uspeli da rekonstruišemo.
10:20
And you can begin to compare it to the genomes
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I može početi da ga upoređuje sa genomima
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 ćete možda želeti da postavite
10:29
is, what happened when we met?
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je, šta se desilo kada smo se sreli?
10:31
Did we mix or not?
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Jesmo li se mešali ili nismo?
10:33
And the way to ask that question
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I način na koji to pitanje može da se postavi
10:35
is to look at the Neanderthal that comes from Southern Europe
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je da se posmatra Neandertalac koji potiče iz Južne Evrope
10:38
and compare it to genomes
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i da se uporedi sa genomima
10:40
of people who live today.
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ljudi koji su danas živi.
10:42
So we then look
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Pa zatim gledamo
10:44
to do this with pairs of individuals,
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da to uradimo sa parovima pojedinaca,
10:46
starting with two Africans,
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počevši od dva Afrikanca,
10:48
looking at the two African genomes,
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posmatrajući dva afrička genoma,
10:50
finding places where they differ from each other,
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pronalazeći mesta na kojima se međusobno razlikuju
10:53
and in each case ask: What is a Neanderthal like?
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i za svaki taj primer postavljamo pitanje: Kako izgleda Neandertalac?
10:56
Does it match one African or the other African?
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Da li se poklapa sa jednim Afrikancem ili sa drugim Afrikancem?
10:59
We would expect there to be no difference,
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Očekivali bismo da tu ne bude razlike,
11:02
because Neanderthals were never in Africa.
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jer Neandertalci nikada nisu bili u Africi.
11:04
They should be equal, have no reason to be closer
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Trebalo bi da su podjednaki, nema razloga da budu bliži
11:07
to one African than another African.
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jednom Afrikancu nego drugom.
11:10
And that's indeed the case.
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I to je zaista i slučaj.
11:12
Statistically speaking, there is no difference
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Posmatrajući statistički, nema razlike
11:14
in how often the Neanderthal matches one African or the other.
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u tome koliko se često Neandertalac poklapa sa jednim ili drugim Afrikancem.
11:18
But this is different
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Ali, uočava se razlika
11:20
if we now look at the European individual and an African.
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ako sada pogledamo pojedinca iz Evrope i jednog Afrikanca.
11:24
Then, significantly more often,
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Tada, statistički značajno češće
11:27
does a Neanderthal match the European
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se Neandertalac poklapa sa Evropljaninom
11:29
rather than the African.
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nego sa Afrikancem.
11:31
The same is true if we look at a Chinese individual
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Isto to važi i ako posmatramo pojedinca iz Kine
11:34
versus an African,
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naspram Afrikanca,
11:36
the Neanderthal will match the Chinese individual more often.
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Neandertalac će se češće poklapati sa kineskom individuom.
11:40
This may also be surprising
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To takođe može biti iznenađujuće,
11:42
because the Neanderthals were never in China.
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jer Neandertalci nikada nisu bili u Kini.
11:44
So the model we've proposed to explain this
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Dakle, model koji predlažemo da bismo to objasnili
11:48
is that when modern humans came out of Africa
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je da, kada su moderni ljudi izašli iz Afrike
11:50
sometime after 100,000 years ago,
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negde pre 100.000 godina,
11:53
they met Neanderthals.
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sreli su se sa Neandertalcima.
11:55
Presumably, they did so first in the Middle East,
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Verovatno se to prvi put desilo na Bliskom Istoku
11:58
where there were Neanderthals living.
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gde su Neandertalci živeli.
12:00
If they then mixed with each other there,
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Ako su se tamo međusobno mešali,
12:02
then those modern humans
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onda bi 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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svima van Afrike
12:08
carried with them this Neanderthal component in their genome
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preneli tu neandertalsku komponentu u svom genomu
12:11
to the rest of the world.
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u ostale delove sveta.
12:13
So that today, the people living outside Africa
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Tako da, danas, ljudi koji žive van Afrike
12:16
have about two and a half percent of their DNA
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imaju oko dva i po procenta svoje DNK
12:19
from Neanderthals.
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od Neandertalaca.
12:21
So having now a Neanderthal genome
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Dakle, sada kad imamo neandertalski genom
12:24
on hand as a reference point
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pri ruci, kao referentnu tačku
12:26
and having the technologies
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i kad imamo tehnologije
12:28
to look at ancient remains
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da ispitujemo drevne ostatke
12:30
and extract the DNA,
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i da ekstrahujemo DNK,
12:32
we can begin to apply them elsewhere in the world.
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možemo početi da ih primenjujemo i drugde u svetu.
12:36
And the first place we've done that is in Southern Siberia
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I prvo mesto na kom smo to uradili je u Južnom Sibiru
12:39
in the Altai Mountains
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u Altajskim planinama
12:41
at a place called Denisova,
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u mestu pod imenom Denisova,
12:43
a cave site in this mountain here,
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u pećinskom nalazištu na toj planini,
12:45
where archeologists in 2008
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gde su arheolozi 2008. godine
12:48
found a tiny little piece of bone --
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našli malecko parče kosti --
12:50
this is a copy of it --
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ovo je kopija toga --
12:52
that they realized came from the last phalanx
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za koje su shvatili da potiče od zadnje falange
12:56
of a little finger of a pinky of a human.
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malog prsta čoveka.
12:59
And it was well enough preserved
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I to parče je bilo dovoljno dobro sačuvano
13:01
so we could determine the DNA from this individual,
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pa smo mogli da odredimo DNK iz ove jedinke,
13:04
even to a greater extent
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i to čak u većem stepenu,
13:06
than for the Neanderthals actually,
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nego za Neandertalce i mogli
13:08
and start relating it to the Neanderthal genome
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smo da počnemo da to upoređujemo sa neandertalskim
13:10
and to people today.
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genomom i sa današnjim ljudima.
13:13
And we found that this individual
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I pronašli smo da ova jedinka
13:15
shared a common origin for his DNA sequences
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deli zajedničke predačke osnove DNK sekvenci
13:18
with Neanderthals around 640,000 years ago.
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sa Neandertalcima, od pre oko 640.000 godina.
13:22
And further back, 800,000 years ago
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A još dalje u prošlost, pre oko 800.000 godina,
13:25
is there a common origin
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se nalaze zajedničke predačke tačke
13:27
with present day humans.
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sa današnjim ljudima.
13:29
So this individual comes from a population
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Dakle, ta jedinka potiče iz populacije
13:31
that shares an origin with Neanderthals,
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koja deli poreklo sa Neandertalcima,
13:34
but far back and then have a long independent history.
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ali daleko u prošlosti, a zatim ide kroz dugu nezavisnu istoriju.
13:37
We call this group of humans,
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Mi imamo naziv za ovu grupu ljudi,
13:39
that we then described for the first time
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koju smo tada opisali po prvi put
13:41
from this tiny, tiny little piece of bone,
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iz ovog majušnog parčeta kosti,
13:43
the Denisovans,
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zovemo ih ljudima iz Denisove,
13:45
after this place where they were first described.
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po mestu na kojem su prvi put opisani.
13:48
So we can then ask for Denisovans
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Pa tako možemo pitati za ljude iz Denisove
13:51
the same things as for the Neanderthals:
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iste stvari kao za Neandertalce:
13:53
Did they mix with ancestors of present day people?
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Da li su se mešali sa 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 ako uporedimo genom ljudi iz Denisove
14:01
to people around the world,
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sa ljudima širom sveta
14:03
we surprisingly find
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iznenađujuće otkriće je
14:05
no evidence of Denisovan DNA
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da nema dokaza o denisovskoj DNK
14:07
in any people living even close to Siberia today.
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ni kod jednog savremenog naroda, čak ni kod onih blizu Sibira.
14:12
But we do find it in Papua New Guinea
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Ali, pronašli smo ih u Papui Novoj Gvineji
14:14
and in other islands in Melanesia and the Pacific.
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i drugim ostrvima u Melaneziji i Pacifiku.
14:18
So this presumably means
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To, po svoj prilici, znači
14:20
that these Denisovans had been more widespread in the past,
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da su ljudi iz Denisove bili u prošlosti šire rasprostranjeni,
14:23
since we don't think that the ancestors of Melanesians
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jer ne smatramo da su preci ljudi iz Melanezije
14:26
were ever in Siberia.
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ikada bili u Sibiru.
14:28
So from studying
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Dakle, putem proučavanja
14:30
these genomes of extinct humans,
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ovih genoma izumrlih ljudi,
14:33
we're beginning to arrive at a picture of what the world looked like
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počinjemo da dobijamo sliku o tome kako je izgledao svet
14:36
when modern humans started coming out of Africa.
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kada su moderni ljudi počeli da izlaze 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 ljudi iz Denisove --
14:44
maybe other forms of humans too
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možda i neke druge forme 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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Još uvek ne znamo sasvim gde su bile granice između ovih ljudi,
14:51
but we know that in Southern Siberia,
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ali znamo da su u Južnom Sibiru,
14:53
there were both Neanderthals and Denisovans
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živeli i Neandertalci i ljudi iz Denisove
14:55
at least at some time in the past.
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bar neko vreme u prošlosti.
14:58
Then modern humans emerged somewhere in Africa,
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Zatim su se moderni ljudi pojavili negde u Africi,
15:01
came out of Africa, presumably in the Middle East.
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izašli su iz Afrike, po svoj prilici na Bliski Istok.
15:04
They meet Neanderthals, mix with them,
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Sreli su Neandertalce, mešali se sa njima,
15:07
continue to spread over the world,
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nastavili su da napreduju širom sveta,
15:10
and somewhere in Southeast Asia,
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i negde u Jugoistočnoj Aziji,
15:13
they meet Denisovans and mix with them
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sreli su ljude iz Denisove i mešali se sa njima
15:15
and continue on out into the Pacific.
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i nastavili su dalje ka Pacifiku.
15:18
And then these earlier forms of humans disappear,
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A onda su ove ranije forme ljudi nestale,
15:21
but they live on a little bit today
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ali su i danas u maloj meri prisutne
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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po tome što ljudi van Afrike imaju dva i po procenta svoje DNK
15:29
from Neanderthals,
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od Neandertalaca,
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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u stvari imaju dodatnih pet procenata otprilike
15:36
from the Denisovans.
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od ljudi iz Denisove.
15:39
Does this then mean that there is after all
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Da li ovo znači da ipak postoji
15:41
some absolute difference
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neka apsolutna razlika
15:43
between people outside Africa and inside Africa
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između ljudi van Afrike i unutar Afrike
15:46
in that people outside Africa
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po tome da ljudi van Afrike
15:48
have this old component in their genome
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imaju ovu staru komponentu u svom genomu
15:50
from these extinct forms of humans,
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od ovih izumrlih ljudski formi,
15:52
whereas Africans do not?
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dok Afrikanci to nemaju?
15:54
Well I don't think that is the case.
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Pa, ja mislim da to nije slučaj.
15:57
Presumably, modern humans
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Po svoj prilici, moderni ljudi
15:59
emerged somewhere in Africa.
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su se pojavili negde u Africi.
16:01
They spread across Africa also, of course,
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Proširili su se kroz Afriku, naravno,
16:04
and there were older, earlier forms of humans there.
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a tamo su postojale starije, ranije forme ljudi.
16:07
And since we mixed elsewhere,
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I budući da smo se mešali na drugim mestima,
16:09
I'm pretty sure that one day,
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prilično sam siguran da ćemo, jednog dana,
16:11
when we will perhaps have a genome
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možda kad budemo imali genom
16:13
of also these earlier forms in Africa,
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i ovih ranijih formi u Africi,
16:15
we will find that they have also mixed
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pronaći da su se i oni mešali
16:17
with early modern humans in Africa.
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sa ranim modernim ljudima u Africi.
16:21
So to sum up,
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Dakle da sumiramo,
16:23
what have we learned from studying genomes
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šta smo naučili putem proučavanja genoma
16:25
of present day humans
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današnjih ljudi
16:27
and extinct humans?
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i izumrlih ljudi?
16:29
We learn perhaps many things,
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Moguće je da smo saznali mnogo stvari,
16:31
but one thing that I find sort of important to mention
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ali jedna stvar za koju smatram da je važno pomenuti
16:36
is that I think the lesson is that we have always mixed.
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po mom mišljenju je ta lekcija da smo se oduvek mešali.
16:39
We mixed with these earlier forms of humans,
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Mešali smo se sa ovim ranijim formama ljudi,
16:41
wherever we met them,
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gde god smo ih sreli,
16:43
and we mixed with each other ever since.
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i mešamo se međusobno od tada do danas.
16:47
Thank you for your attention.
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Hvala vam na pažnji.
16:49
(Applause)
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(aplauz)
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