What is so special about the human brain? | Suzana Herculano-Houzel

783,229 views ・ 2013-11-26

TED


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Prevodilac: Jelena Jevtić Lektor: Mile Živković
00:12
What is so special about the human brain?
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Zašto je toliko poseban ljudski mozak?
00:15
Why is it that we study other animals
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Zašto mi proučavamo druge životinje,
00:17
instead of them studying us?
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umesto da one proučavaju nas?
00:19
What does a human brain have or do
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Šta to ljudski mozak ima ili radi
00:21
that no other brain does?
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što nijedan drugi mozak ne može?
00:23
When I became interested in these questions about 10 years ago,
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Kada sam počela da se zanimam za ova pitanja pre desetak godina,
00:26
scientists thought they knew what different brains were made of.
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naučnici su mislili da znaju kakvog su sastava različiti mozgovi.
00:28
Though it was based on very little evidence,
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Iako je, u osnovi, bilo malo dokaza
00:30
many scientists thought that all mammalian brains,
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mnogi naučnici su mislili da su mozgovi sisara,
00:32
including the human brain,
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uključujući i ljudski mozak,
00:34
were made in the same way,
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potpuno isto načinjeni,
00:35
with a number of neurons that was always
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sa brojem neurona koji je oduvek
00:37
proportional to the size of the brain.
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bio proporcionalan veličini mozga.
00:39
This means that two brains of the same size,
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To znači da dva mozga istih veličina,
00:41
like these two, with a respectable 400 grams,
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kao ova dva, od pristojnih 400 grama,
00:45
should have similar numbers of neurons.
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treba da imaju isti broj neurona.
00:47
Now, if neurons are the functional
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Sada, ako su neuroni funkcionalne
00:49
information processing units of the brain,
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prenosne jedinice informacija,
00:52
then the owners of these two brains
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onda vlasnici ova dva mozga
00:54
should have similar cognitive abilities.
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treba da imaju iste kognitivne sposobnosti.
00:56
And yet, one is a chimp,
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A ipak, jedan vlasnik je šimpanza,
00:59
and the other is a cow.
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a drugi vlasnik je krava.
01:01
Now maybe cows have a really rich
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Sada, možda krave imaju jako bogat
01:04
internal mental life and are so smart
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unutrašnji, duševni život i toliko su pametne
01:06
that they choose not to let us realize it,
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da su odlučile da nam ne dozvole da to shvatimo,
01:10
but we eat them.
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ali mi njih jedemo.
01:11
I think most people will agree
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Mislim da bi se većina ljudi složila
01:13
that chimps are capable of much more complex,
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da su šimpanze sposobne za mnogo složenije,
01:15
elaborate and flexible behaviors than cows are.
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detaljnije i prilagodljivije ponašanje nego krave.
01:18
So this is a first indication that the
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Tako da je ovo prvi pokazatelj
01:20
"all brains are made the same way" scenario
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da scenario tipa: "Svi mozgovi su isto načinjeni",
01:22
is not quite right.
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nije baš prihvatljiv.
01:24
But let's play along.
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Ali, hajde da i mi pretpostavimo isto.
01:25
If all brains were made the same way
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Ako su svi mozgovi načinjeni isto,
01:27
and you were to compare animals with brains of different sizes,
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i na vama je da poredite životinje sa različitom veličinom mozga,
01:30
larger brains should always have more neurons
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veći mozgovi bi uvek trebalo da imaju više neurona
01:32
than smaller brains, and the larger the brain,
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od manjih i što je mozak veći,
01:34
the more cognitively able its owner should be.
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veće bi trebale da budu i kognitivne sposobnosti njegovog vlasnika.
01:37
So the largest brain around should also be
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Tako da najveći mozak treba da bude
01:39
the most cognitively able.
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i najviše kognitivno sposoban.
01:42
And here comes the bad news:
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Ali, evo loših vesti.
01:43
Our brain, not the largest one around.
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Naš mozak nije najveći u okruženju.
01:46
It seems quite vexing.
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Zvuči prilično uznemirujuće.
01:47
Our brain weighs between 1.2 and 1.5 kilos,
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Naš mozak je težine između 1,2 i 1,5 kilograma,
01:50
but elephant brains weigh between four and five kilos,
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ali mozak slona je težine od četiri do pet kilograma,
01:54
and whale brains can weigh up to nine kilos,
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a mozak kita može biti težine i do 9 kilograma,
01:56
which is why scientists used to resort to saying
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i zato su naučnici imali običaj da pribegavaju tvrdnji,
02:01
that our brain must be special
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da naši mozgovi mora da su posebni,
02:03
to explain our cognitive abilities.
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jer to objašnjava naše kognitivne sposobnosti.
02:06
It must be really extraordinary,
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Mora da je zaista izvanredan,
02:09
an exception to the rule.
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izuzetak od pravila.
02:11
Theirs may be bigger, but ours is better,
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Njihov je možda veći, ali naš je bolji,
02:14
and it could be better, for example,
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i može biti bolji, na primer,
02:16
in that it seems larger than it should be,
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u tome, jer je veći nego što treba da bude,
02:18
with a much larger cerebral cortex than we should have
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sa mnogo većim cerebralnim korteksom nego što bi trebalo,
02:21
for the size of our bodies.
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u odnosu na veličinu našeg tela.
02:22
So that would give us extra cortex
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Tako da nam ostaje višak korteksa
02:24
to do more interesting things than just operating the body.
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za neke interesantnije stvari od samog funkcionisanja tela.
02:27
That's because the size of the brain
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Veličina mozga
02:29
usually follows the size of the body.
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obično je srazmerna veličini tela.
02:31
So the main reason for saying that
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Tako da glavni razlog što kažemo
02:33
our brain is larger than it should be
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da je naš mozak veći nego što bi trebalo
02:35
actually comes from comparing ourselves
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u stvari dolazi iz poređenja ljudi
02:37
to great apes.
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sa velikim majmunima.
02:39
Gorillas can be two to three times larger than we are,
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Gorile mogu biti dva ili tri puta veće nego što smo mi,
02:41
so their brains should also be larger than ours,
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tako da bi njihovi mozgovi trebalo isto tako da budu veći od naših,
02:44
but instead it's the other way around.
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ali u stvari je obrnuto.
02:46
Our brain is three times larger than a gorilla brain.
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Naš mozak je tri puta veći od mozga gorile.
02:49
The human brain also seems special
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Ljudski mozak se isto tako čini poseban,
02:51
in the amount of energy that it uses.
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i u količini energije koju koristi.
02:53
Although it weighs only two percent of the body,
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Iako je težine samo dva procenta od ukupne težine tela,
02:56
it alone uses 25 percent of all the energy
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koristi 25 procenata ukupne energije
02:59
that your body requires to run per day.
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koju vaše telo zahteva da bi funkcionisalo u jednom danu.
03:02
That's 500 calories out of a total of 2,000 calories,
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To je 500 kalorija od ukupnih 2000 kalorija,
03:05
just to keep your brain working.
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samo da bi mozak bio u aktivnom stanju.
03:07
So the human brain is larger than it should be,
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Znači, ljudski mozak je veći nego što bi trebalo da bude,
03:10
it uses much more energy than it should,
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koristi mnogo više energije nego što je potrebno -
03:12
so it's special.
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znači da je poseban.
03:14
And this is where the story started to bother me.
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I evo gde je priča počela da mi smeta.
03:16
In biology, we look for rules
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U biologiji, mi tražimo pravila
03:18
that apply to all animals and to life in general,
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koja primenjujemo na životinje i život uopšte,
03:21
so why should the rules of evolution
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i zašto se onda pravila evolucije
03:23
apply to everybody else but not to us?
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primenjuju na sve ostale, ali ne i na nas?
03:26
Maybe the problem was with the basic assumption
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Možda je problem bio u osnovnoj pretpostavci
03:29
that all brains are made in the same way.
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da su svi mozgovi istog sastava.
03:30
Maybe two brains of a similar size
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Možda, dva mozga istih veličina,
03:32
can actually be made of very different numbers of neurons.
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u stvari, mogu biti sastavljeni od različitog broja neurona.
03:35
Maybe a very large brain
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Možda, veoma veliki mozak
03:36
does not necessarily have more neurons
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nema i veći broj neurona
03:38
than a more modest-sized brain.
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od manjeg mozga.
03:40
Maybe the human brain actually has the most neurons
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Možda ljudski mozak u stvari ima najviše neurona
03:43
of any brain, regardless of its size,
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od bilo kog mozga, nezavisno od veličine,
03:46
especially in the cerebral cortex.
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posebno u cerebralnom korteksu.
03:48
So this to me became
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Tako da je ovo postalo za mene
03:50
the important question to answer:
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važno pitanje na koje treba da dam odgovor:
03:51
how many neurons does the human brain have,
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koliko neurona ljudski mozak ima,
03:54
and how does that compare to other animals?
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i kako se to može porediti sa drugim životinjama?
03:56
Now, you may have heard or read somewhere
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Možda ste čuli ili pročitali negde
03:59
that we have 100 billion neurons,
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da mi imamo 100 milijardi neurona,
04:01
so 10 years ago, I asked my colleagues
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i pre 10 godina, pitala sam svoje kolege
04:03
if they knew where this number came from.
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da li možda znaju otkud ova brojka.
04:05
But nobody did.
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Ali niko nije znao.
04:06
I've been digging through the literature
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Malo sam kopala po literaturi
04:08
for the original reference for that number,
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tražeći originalnu referencu za tu brojku,
04:10
and I could never find it.
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i nikada je nisam mogla pronaći.
04:11
It seems that nobody had actually ever counted
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Izgleda da niko nije, u stvari, nikada izbrojao
04:14
the number of neurons in the human brain,
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broj neurona u ljudskom mozgu,
04:16
or in any other brain for that matter.
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ili bilo kom drugom mozgu.
04:18
So I came up with my own way to count cells in the brain,
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Tako da sam pronašla sopstveni način da izbrojim ćelije u mozgu,
04:22
and it essentially consists of
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i u osnovi, sastoji se u
04:24
dissolving that brain into soup.
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rastvaranju mozga u supu.
04:27
It works like this:
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To ovako funkcioniše:
04:29
You take a brain, or parts of that brain,
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mozak, ili delove mozga,
04:32
and you dissolve it in detergent,
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rastvorite u deterdžentu,
04:34
which destroys the cell membranes
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koji uništava ćelijske membrane
04:35
but keeps the cell nuclei intact,
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ali ćelijska jezgra ostaju netaknuta,
04:38
so you end up with a suspension of free nuclei
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i na kraju završite sa suspenzijom slobodnih jezgara
04:41
that looks like this,
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koja izgleda ovako,
04:43
like a clear soup.
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kao bistra supa.
04:44
This soup contains all the nuclei
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Ova supa sadrži sva jezgra
04:46
that once were a mouse brain.
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koja su nekada bila u mozgu miša.
04:48
Now, the beauty of a soup is that because it is soup,
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Sada, prednosti supe su te
04:51
you can agitate it and make those nuclei
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da je možete promućkati i naterati jezgra
04:54
be distributed homogeneously in the liquid,
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da se pravilno rasporede u tečnosti,
04:56
so that now by looking under the microscope
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tako da posmatranjem pod mikroskopom
04:58
at just four or five samples of this homogeneous solution,
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samo četiri ili pet uzoraka ovog homogenog rastvora
05:02
you can count nuclei, and therefore tell
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možete da izbrojite jezgra, a potom i kažete
05:05
how many cells that brain had.
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od koliko ćelija se mozak sastojao.
05:06
It's simple, it's straightforward,
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Jednostavno je i direktno,
05:08
and it's really fast.
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i veoma brzo.
05:09
So we've used that method to count neurons
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Tako da smo mi koristili tu metodu da izbrojimo neurone
05:11
in dozens of different species so far,
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različitih vrsta,
05:14
and it turns out that all brains
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i ispostavlja se da nisu svi mozgovi
05:15
are not made the same way.
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istog sastava.
05:18
Take rodents and primates, for instance:
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Uzmite glodare i primate, na primer.
05:20
In larger rodent brains, the average size
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U većim mozgovima glodara, prosečna veličina
05:22
of the neuron increases,
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neurona raste,
05:24
so the brain inflates very rapidly
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tako da se mozak uvećava veoma brzo
05:27
and gains size much faster than it gains neurons.
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i uvećava se mnogo brže nego što postiže veći broj neurona.
05:30
But primate brains gain neurons
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Ali kod primata, mozak postiže veći broj neurona
05:32
without the average neuron becoming any larger,
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bez uvećavanja samog neurona,
05:34
which is a very economical way
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što je prilično ekonomičan način
05:35
to add neurons to your brain.
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dodavanja neurona vašem mozgu.
05:37
The result is that a primate brain
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Kao rezultat, mozak primata
05:39
will always have more neurons than a rodent brain of the same size,
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će uvek imati više neurona od mozga glodara koji je iste veličine,
05:42
and the larger the brain,
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i što je mozak veći,
05:44
the larger this difference will be.
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veća će biti i razlika.
05:46
Well, what about our brain then?
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A, šta je onda sa našim mozgovima?
05:48
We found that we have, on average,
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Otkrili smo da mi u proseku imamo
05:50
86 billion neurons,
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86 milijardi neurona,
05:51
16 billion of which are in the cerebral cortex,
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16 milijardi su u cerebralnom korteksu,
05:54
and if you consider that the cerebral cortex
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i ako uzmete u obzir da je cerebralni korteks
05:56
is the seat of functions like
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glavni za funkcije, kao što su:
06:00
awareness and logical and abstract reasoning,
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svesnost, logično i apstraktno rezonovanje,
06:03
and that 16 billion is the most neurons
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i da je 16 milijardi najveći broj neurona
06:06
that any cortex has,
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koji bilo koji korteks sadrži,
06:08
I think this is the simplest explanation
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mislim da je ovo najjednostavnije objašnjenje
06:10
for our remarkable cognitive abilities.
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naših izvanrednih kognitivnih sposobnosti.
06:13
But just as important is what the 86 billion neurons mean.
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Ali isto tako važno je, šta znači uopšte broj od 86 milijardi neurona.
06:16
Because we found that the relationship
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Zato što smo pronašli da veza između
06:18
between the size of the brain and its number of neurons
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veličine mozga i broja neurona
06:20
could be described mathematically,
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može biti matematički opisana,
06:22
we could calculate what a human brain
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možemo pokazati kako bi ljudski mozak
06:24
would look like if it was made like a rodent brain.
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izgledao da je po sastavu kao mozak glodara.
06:27
So, a rodent brain with 86 billion neurons
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Tako da bi mozak glodara sa 86 milijardi neurona
06:30
would weigh 36 kilos.
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bio težine 36 kilograma.
06:33
That's not possible.
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To nije moguće.
06:35
A brain that huge would be crushed
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Toliki mozak bi bio uništen
06:37
by its own weight,
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svojom težinom,
06:38
and this impossible brain would go
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i takav mozak bi išao
06:40
in the body of 89 tons.
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uz telo težine od 89 tona.
06:44
I don't think it looks like us.
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Mislim da to ne liči na nas.
06:46
So this brings us to a very important conclusion already,
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Tako da nas ovo već dovodi do važnog zaključka,
06:48
which is that we are not rodents.
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koje glasi: mi nismo glodari.
06:51
The human brain is not a large rat brain.
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Mozak ljudi nije veliki mozak pacova.
06:54
Compared to a rat, we might seem special, yes,
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U poređenju sa pacovima, mi možda izgledamo posebno,
06:57
but that's not a fair comparison to make,
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ali to nije pravedno poređenje
06:59
given that we know that we are not rodents.
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znajući da mi nismo glodari.
07:01
We are primates,
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Mi smo primati,
07:02
so the correct comparison is to other primates.
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tako da je pravilno poređenje ono sa drugim primatima.
07:05
And there, if you do the math,
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I tu, ako odradite matematiku,
07:06
you find that a generic primate
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pronalazite da će primat
07:09
with 86 billion neurons
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sa 86 milijardi neurona
07:11
would have a brain of about 1.2 kilos,
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imati mozak težine oko 1,2 kilograma,
07:14
which seems just right,
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što je i sasvim dovoljno,
07:16
in a body of some 66 kilos,
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1972
za nekoga ko je težine od nekih 66 kilograma,
07:18
which in my case is exactly right,
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što je u mom slučaju potpuno tačno,
07:21
which brings us to a very unsurprising
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i to nas dovodi do veoma poznatog,
07:23
but still incredibly important conclusion:
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ali ipak neverovatno značajnog zaključka:
07:26
I am a primate.
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Ja sam primat.
07:28
And all of you are primates.
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I svi vi ste primati.
07:30
And so was Darwin.
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Kao što je i Darvin bio.
07:32
I love to think that Darwin would have really appreciated this.
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Volim da mislim da bi Darvin zaista cenio ovo.
07:35
His brain, like ours,
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1967
Njegov mozak, kao i naš
07:37
was made in the image of other primate brains.
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napravljen je po ugledu na druge primate.
07:41
So the human brain may be remarkable, yes,
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Tako da ljudski mozak možda jeste izvanredan, da,
07:43
but it is not special in its number of neurons.
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ali nije poseban u pogledu broja neurona.
07:46
It is just a large primate brain.
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Samo je to jedan veliki mozak primata.
07:48
I think that's a very humbling and sobering thought
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Mislim da je to jedna veoma skromna i trezvena misao,
07:51
that should remind us of our place in nature.
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koja treba da nas podseti koje je naše mesto u prirodi.
07:54
Why does it cost so much energy, then?
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Zašto je onda potrebno utrošiti toliko energije?
07:56
Well, other people have figured out
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Neki ljudi su pronašli
07:58
how much energy the human brain
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1503
koliko je energije potrebno ljudskom mozgu
07:59
and that of other species costs,
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i mozgu nekih drugih vrsta,
08:01
and now that we knew how many neurons
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i sada kada znamo koliko neurona
08:02
each brain was made of, we could do the math.
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svaki mozak ima, možemo primeniti matematiku.
08:05
And it turns out that both human
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Ispostavlja se da je i za ljudske
08:07
and other brains cost about the same,
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i za mozgove drugih vrsta, utrošak isti,
08:09
an average of six calories per billion neurons per day.
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prosečno šest kalorija na milijardu neurona, dnevno.
08:13
So the total energetic cost of a brain
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Tako da je ukupni, energetski utrošak
08:15
is a simple, linear function
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2034
jednostavna, linearna funkcija
08:17
of its number of neurons,
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broja neurona,
08:19
and it turns out that the human brain
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i ispostavilo se da ljudski mozak
08:21
costs just as much energy as you would expect.
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troši onoliko energije koliko se i očekivalo.
08:25
So the reason why the human brain
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Tako da je razlog zbog kojeg ljudski mozak
08:27
costs so much energy is simply because
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troši toliko energije, jednostavan,
08:28
it has a huge number of neurons,
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1983
jer ima veliki broj neurona,
08:30
and because we are primates
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i zato što smo mi primati
08:32
with many more neurons for a given body size
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2499
sa mngo većim brojem neurona u odnosu na veličinu tela
08:34
than any other animal,
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od bilo koje druge vrste,
08:36
the relative cost of our brain is large,
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3540
relativna potrošnja našeg mozga je ogromna
08:39
but just because we're primates, not because we're special.
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ali samo zato jer smo mi primati, ne zato što smo posebni.
08:42
Last question, then:
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Poslednje pitanje, onda:
08:44
how did we come by this remarkable number of neurons,
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3115
kako smo se mi zadesili sa ovako velikim brojem neurona,
08:47
and in particular, if great apes
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527278
1900
iako su veliki majmuni
08:49
are larger than we are,
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1555
veći od nas,
08:50
why don't they have a larger brain than we do, with more neurons?
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3765
zašto oni nemaju veći mozak, sa više neurona?
08:54
When we realized how much expensive it is
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2090
Kada smo shvatili koliko je zahtevno
08:56
to have a lot of neurons in the brain, I figured,
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2333
imati puno neurona u mozgu,
08:58
maybe there's a simple reason.
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2003
možda je razlog jednostavan.
09:00
They just can't afford the energy
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1683
Oni ne mogu da priušte dovoljno energije
09:02
for both a large body and a large number of neurons.
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i za ogromna tela i za veliki broj neurona.
09:05
So we did the math.
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1429
Tako da smo odradili matematiku.
09:06
We calculated on the one hand
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1600
Izračunali smo, sa jedne strane,
09:08
how much energy a primate gets per day
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1941
koliko je energije potrebno sisaru dnevno,
09:10
from eating raw foods,
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1350
ako se hrane sirovom hranom,
09:11
and on the other hand, how much energy
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2037
i sa druge strane, koliko energije
09:13
a body of a certain size costs
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za telo određene veličine.
09:15
and how much energy a brain of a certain number of neurons costs,
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3387
i koliko je energije potrebno mozgu koji ima određeni broj neurona,
09:19
and we looked for the combinations
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1489
i tragali smo za kombinacijom
09:20
of body size and number of brain neurons
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2411
veličine tela i broja neurona
09:22
that a primate could afford
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koje primat sebi može priuštiti
09:24
if it ate a certain number of hours per day.
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2548
ako jede određen broj sati dnevno.
09:26
And what we found is that
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1816
I ono što smo pronašli je to
09:28
because neurons are so expensive,
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1712
da su neuroni veoma skupi.
09:30
there is a tradeoff between body size and number of neurons.
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Postoji kompromis između veličine tela i broja neurona.
09:33
So a primate that eats eight hours per day
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2951
Tako da primat koji jede osam sati dnevno
09:36
can afford at most 53 billion neurons,
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3024
može najviše priuštiti 53 milijarde neurona,
09:39
but then its body cannot be any bigger
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1727
ali onda telo ne može postati teže
09:41
than 25 kilos.
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1954
od 25 kilograma.
09:43
To weigh any more than that,
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1701
Veća težina
09:45
it has to give up neurons.
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1769
znači i manji broj neurona.
09:46
So it's either a large body
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2653
Tako da ili je telo veće
09:49
or a large number of neurons.
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ili je veći broj neurona.
09:50
When you eat like a primate,
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1365
Kada se hranite kao primati,
09:52
you can't afford both.
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2236
ne možete sebi priuštiti i jedno i drugo.
09:54
One way out of this metabolic limitation
256
594556
1964
Jedini izlaz iz ovakvih postavljenih metaboličkih granica
09:56
would be to spend even more hours per day eating,
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3401
bi bio: još više sati utrošiti na ishranu,
09:59
but that gets dangerous,
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1363
ali to već postaje opasno,
10:01
and past a certain point, it's just not possible.
259
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2719
i posle određene granice, nije ni moguće.
10:04
Gorillas and orangutans, for instance,
260
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1537
Gorile i orangutani, na primer,
10:05
afford about 30 billion neurons
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1923
mogu priuštiti sebi 30 milijardi neurona,
10:07
by spending eight and a half hours per day eating,
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2966
provodeći dnevno 8 i po sati u jelu,
10:10
and that seems to be about as much as they can do.
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3116
i to je izgleda i najviše što mogu.
10:13
Nine hours of feeding per day
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1791
Devet sati hranjenja dnevno,
10:15
seems to be the practical limit for a primate.
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izgleda da je realna granica, koja je postavljena za primate.
10:18
What about us?
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Šta je sa nama?
10:20
With our 86 billion neurons
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1600
Sa naših 86 milijardi neurona
10:21
and 60 to 70 kilos of body mass,
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3035
i od 60 do 70 kilograma telesne mase,
10:25
we should have to spend over nine hours
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3561
trebalo bi da provodimo preko devet sati
10:28
per day every single day feeding,
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3575
svakog dana, hraneći se,
10:32
which is just not feasible.
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2039
što prosto, nije izvodljivo.
10:34
If we ate like a primate,
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1834
Da jedemo kao primati,
10:36
we should not be here.
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2253
ne bi trebalo da budemo ovde.
10:38
How did we get here, then?
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Kako smo u stvari dospeli ovde, onda?
10:40
Well, if our brain costs just as much energy
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2735
Pa, ako našim mozgovima treba energije
10:43
as it should, and if we can't spend
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1723
koliko je potrebno, i ako ne možemo da provedemo
10:44
every waking hour of the day feeding,
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3674
svaki sat tokom dana, hraneći se
10:48
then the only alternative, really,
278
648554
1911
onda je jedina mogućnost, zaista
10:50
is to somehow get more energy
279
650465
1958
da nekako dobijemo više energije
10:52
out of the same foods.
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652423
1953
iz iste hrane.
10:54
And remarkably, that matches exactly
281
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3800
I izvanredno, to se poklapa upravo
10:58
what our ancestors are believed to have invented
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3037
sa otkrićem naših predaka
11:01
one and a half million years ago,
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1839
pre milion i po godina,
11:03
when they invented cooking.
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2782
kada su i izumeli kuvanje.
11:05
To cook is to use fire
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1970
Kuvanje znači koristiti vatru
11:07
to pre-digest foods outside of your body.
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3800
da bi se hrana mogla bolje svariti.
11:11
Cooked foods are softer, so they're easier to chew
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2606
Kuvana hrana je mekša, tako da je lakša da se žvaće
11:14
and to turn completely into mush in your mouth,
288
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2563
i potpuno se pretvara u kašu u ustima,
11:16
so that allows them to be completely digested
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2152
tako da može biti potpuno svarena
11:18
and absorbed in your gut,
290
678925
1436
i apsorbovana u stomaku,
11:20
which makes them yield much more energy in much less time.
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3655
što za kraće vreme donosi mnogo više energije u mnogo kraćem vremenu.
11:24
So cooking frees time for us to do
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2489
Tako da kuvanje nama štedi vreme da bismo radili
11:26
much more interesting things with our day
293
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2062
neke mnogo interesantnije stvari u našem danu
11:28
and with our neurons
294
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1480
i sa našim neuronima,
11:30
than just thinking about food,
295
690047
1905
da ne bismo samo razmišljali o hrani,
11:31
looking for food, and gobbling down food
296
691952
1704
tragali za hranom i gutali hranu
11:33
all day long.
297
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1225
po čitav dan.
11:34
So because of cooking, what once was
298
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2499
I tako, zbog kuvanja, ono što je
11:37
a major liability, this large,
299
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2353
nekada bila velika odgovornost, ovako veliki
11:39
dangerously expensive brain with a lot of neurons,
300
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3033
veoma skup mozak sa puno neurona,
11:42
could now become a major asset,
301
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2036
sada može postati naše glavno oruđe,
11:44
now that we could both afford the energy for a lot of neurons
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3251
sad kada možemo priuštiti i energiju za puno neurona
11:48
and the time to do interesting things with them.
303
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2503
i vreme, da bismo uradili zanimljive stvari sa njima.
11:50
So I think this explains why the human brain
304
710559
1974
Tako da ja mislim ovo objašnjava zašto je ljudski mozak
11:52
grew to become so large so fast in evolution,
305
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3240
tako brzo postao razvijen tokom evolucije,
11:55
all of the while remaining just a primate brain.
306
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3897
a sve vreme ostajući samo mozak primata.
11:59
With this large brain now affordable by cooking,
307
719670
2774
Sa ovako velikim mozgom, kojeg možemo i koristiti, zahvaljujući kuvanju,
12:02
we went rapidly from raw foods to culture,
308
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2913
munjevito smo prešli sa sirove hrane na kulture,
12:05
agriculture, civilization, grocery stores,
309
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2606
poljoprivredu, civilizaciju, bakalnice,
12:07
electricity, refrigerators,
310
727963
1625
elektricitet, frižidere,
12:09
all of those things that nowadays
311
729588
1607
sve te stvari koje nam danas
12:11
allow us to get all the energy we need
312
731195
2042
omogućavaju da priuštimo svu potrebnu energiju
12:13
for the whole day in a single sitting
313
733237
2782
za ceo dan, samo u jednom obroku
12:16
at your favorite fast food joint.
314
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2954
u omiljenom lancu brze hrane.
12:18
So what once was a solution
315
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2437
Tako da, ono što je nekada bilo rešenje,
12:21
now became the problem,
316
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1699
sada postaje problem,
12:23
and ironically, we look for the solution in raw food.
317
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5517
i ironično, to rešenje tražimo u sirovoj hrani.
12:28
So what is the human advantage?
318
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2556
I šta je prednost ljudi?
12:31
What is it that we have
319
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1503
Šta je to što mi imamo,
12:32
that no other animal has?
320
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2535
a nijedna druga životinja nema?
12:35
My answer is that we have the largest number
321
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2348
Moj odgovor je da imamo najveći broj
12:37
of neurons in the cerebral cortex,
322
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1472
neurona u cerebralnom korteksu,
12:39
and I think that's the simplest explanation
323
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1844
i mislim da je to najjednostavnije objašnjenje
12:40
for our remarkable cognitive abilities.
324
760884
2013
za naše izuzetne kognitivne sposobnosti.
12:42
And what is it that we do that no other animal does,
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3227
A šta je ono što mi radimo, a nijedna druga životinja ne radi
12:46
and which I believe was fundamental
326
766124
1969
i što mislim da je bilo fundamentalno
12:48
to allow us to reach that large,
327
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3083
da bismo uopšte mogli da dosegnemo taj veliki,
12:51
largest number of neurons in the cortex?
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771176
2222
najveći broj neurona u moždanoj kori?
12:53
In two words, we cook.
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2215
Dve reči: mi kuvamo.
12:55
No other animal cooks its food. Only humans do.
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775613
3566
Nijedna druga životinja ne kuva svoju hranu. Samo ljudi to rade.
12:59
And I think that's how we got to become human.
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2870
I ja mislim da smo upravo tako mi i postali ljudi.
13:02
Studying the human brain changed the way I think about food.
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2460
Proučavanje ljudskog mozga je promenilo način na koji razmišljam o hrani.
13:04
I now look at my kitchen,
333
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1645
Sada pogledam u svoju kuhinju
13:06
and I bow to it,
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1470
i klanjam se,
13:07
and I thank my ancestors for coming up
335
787624
1705
i zahvaljujem našim precima što su nabasali
13:09
with the invention that probably made us humans.
336
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1900
na otkriće koje nas je verovatno i načinilo ljudima.
13:11
Thank you very much.
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2132
Hvala vam mnogo.
13:13
(Applause)
338
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6353
(Aplauz)
About this website

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