Interestingly, Charles Darwin was born a very lightly pigmented man, in a moderately-to-darkly pigmented world. Over the course of his life, Darwin had great privilege. He lived in a fairly wealthy home. He was raised by very supportive and interested parents. And when he was in his 20s he embarked upon a remarkable voyage on the ship the Beagle. And during the course of that voyage, he saw remarkable things: tremendous diversity of plants and animals, and humans. And the observations that he made on that epic journey were to be eventually distilled into his wonderful book, "On the Origin of Species," published 150 years ago.
Zanimljivo je da je Čarls Darvin rođen kao veoma svetlo pigmentiran čovek, u ovom umereno do tamno pigmentiranom svetu. Tokom svog života, Darvin je imao sjajnu privilegiju. Živeo je u dobrostojećoj porodici. Podizali su ga jako podržavajući i zainteresovani roditelji. I kada je bio u svojim dvadesetim godinama krenuo je na neverovatan put brodom "Bigl". I tokom tog puta, video je neverovatne stvari. Ogromnu raznolikost biljaka i životinja i ljudi. I zapažanja koja je načinio tokom tog svog epskog puta, bila su naknadno razrađena u njegovoj predivnoj knjizi, "Poreklo vrsta", objavljenoj pre 150 godina.
Now what is so interesting and to some, the extent, what's a bit infamous about "The Origin of Species," is that there is only one line in it about human evolution. "Light will be thrown on the origin of man and his history." It wasn't until much longer, much later, that Darwin actually spoke and wrote about humans.
E sada, šta je to tako interesantno i po nekima, pomalo nepopularno o "Poreklu vrsta", je to da postoji samo jedan red u knjizi o ljudskoj evoluciji. Svetlo će tek biti bačeno na poreklo čoveka i na njegovu istoriju. Tek nakon mnogo vremena, mnogo kasnije, Darvin je počeo da priča i piše o ljudima.
Now in his years of traveling on the Beagle, and from listening to the accounts or explorers and naturalists, he knew that skin color was one of the most important ways in which people varied. And he was somewhat interested in the pattern of skin color. He knew that darkly pigmented peoples were found close to the equator; lightly pigmented peoples, like himself, were found closer to the poles.
Tokom godina njegovog putovanja "Biglom", i slušanja izveštaja raznih prirodnjaka i istraživača, on je znao da je boja kože jedan od najznačajnijih načina na koji se ljudi međusobno razlikuju. Na neki način on je bio zainteresovan za vrste obojenosti kože. Znao je da su tamnije pigmentirani narodi nađeni bliže ekvatoru. Svetlije pigmentirani, kao što je i on sam bio, bili su bliže polovima.
So what did he make of all this? Well he didn't write anything about it in The Origin of Species. But much later, in 1871, he did have something to say about it. And it was quite curious. He said, "Of all the differences between the races of men, the color of the skin is the most conspicuous and one of the best marked." And he went on to say, "These differences do not coincide with corresponding differences in climate." So he had traveled all around. He had seen people of different colors living in different places. And yet he rejected the idea that human skin pigmentation was related to the climate.
I šta je on mislio o tome? Pa, nije o tome ništa napisao u "Poreklu vrsta". Ali dosta kasnije, 1871., imao je nešto da kaže na tu temu. I to je bilo prilično interesantno. Rekao je, "Od svih razlika koje postoje između rasa ljudi, boja kože je najizražajnija i najbolje označena." I u nastavku je rekao, "Ove razlike se ne podudaraju sa odgovarajućim razlikama u klimi." On je putovao svuda unaokolo. Video je ljude različitih boja koji žive na različitim mestima. Pa ipak je odbacio ideju da je ljudska pigmentacija povezana sa klimom.
If only Darwin lived today. If only Darwin had NASA. Now, one of the wonderful things that NASA does is it puts up a variety of satellites that detect all sort of interesting things about our environment. And for many decades now there have been a series of TOMS satellites that have collected data about the radiation of the Earth's surface. The TOMS 7 satellite data, shown here, show the annual average ultraviolet radiation at the Earth's surface. Now the really hot pink and red areas are those parts of the world that receive the highest amounts of UV during the year. The incrementally cooler colors -- blues, greens, yellows, and finally grays -- indicate areas of much lower ultraviolet radiation.
Da je smo Darvin živ danas. Da je samo imao NASA. Jedna od divnih stvari koje NASA radi je to da postavlja različite satelite koji detektuju svakakve interesantne stvari o našem okruženju. I tokom mnogo dekada postoje serije TOMS satelita koji sakupljaju podatke o radijaciji Zemljine površine. TOMS 7 satelitski podaci, vidimo ovde, pokazuju prosečno godišnje ultravioletno zračenje Zemljine površine. Jako pink i crvena područja su oni delovi sveta koji primaju najveće količine UV zračenja tokom godine. Hladnije boje, plava, zelena, žuta i najzad siva, ukazuju na područja sa nižom ultravioletnom radijacijom.
What's significant to the story of human skin pigmentation is just how much of the Northern Hemisphere is in these cool gray zones. This has tremendous implications for our understanding of the evolution of human skin pigmentation. And what Darwin could not appreciate, or didn't perhaps want to appreciate at the time, is that there was a fundamental relationship between the intensity of ultraviolet radiation and skin pigmentation. And that skin pigmentation itself was a product of evolution. And so when we look at a map of skin color, and predicted skin color, as we know it today, what we see is a beautiful gradient from the darkest skin pigmentations toward the equator, and the lightest ones toward the poles.
Ono što je značajno u priči o ljudskoj pigmentaciji jeste to koliki je deo severne hemisfere u ovim hladno sivim zonama. Ovo ima ogromne implikacije za naše razumevanje evolucije ljudske pigmentacije kože. Ono što Darvin nije cenio, ili nije želeo da uzme u obzir u to vreme, jeste to da postoji fundamentalna veza između intenziteta ultravioletne radijacije i pigmentacije kože. I da je pigmentacija kože produkt evolucije. I kada pogledamo mapu boje kože i kada predviđamo boju kože, kao što to znamo danas, ono što vidimo je divna gradacija od tamnije pigmentacije oko ekvatora, do svetlije kod polova.
What's very, very important here is that the earliest humans evolved in high-UV environments, in equatorial Africa. The earliest members of our lineage, the genus Homo, were darkly pigmented. And we all share this incredible heritage of having originally been darkly pigmented, two million to one and half million years ago.
Ono što je veoma značajno ovde je da su najraniji humanoidi evoluirali u uslovima visokog UV zračenja, u ekvatorijalnoj Africi. Najraniji članovi naše vrste, roda Homo, su bili tamno pogmentirani. I mi svi delimo to neverovantno nasleđe toga da smo prvobitno bili tamno pigmentirani, od dva miliona do milion ipo godina ranije.
Now what happened in our history? Let's first look at the relationship of ultraviolet radiation to the Earth's surface. In those early days of our evolution, looking at the equator, we were bombarded by high levels of ultraviolet radiation. The UVC, the most energetic type, was occluded by the Earth's atmosphere. But UVB and UVA especially, came in unimpeded. UVB turns out to be incredibly important. It's very destructive, but it also catalyzes the production of vitamin D in the skin, vitamin D being a molecule that we very much need for our strong bones, the health of our immune system, and myriad other important functions in our bodies.
E sad, šta se desilo u našoj istoriji? Hajde da prvo pogledamo vezu ultravioletnog zračenja na Zemljinu površinu. U tim ranim danima naše evolucije, gledajući ekvator, bili smo bombardovani visokim nivoima ultravioletnog zračenja. UVC, tip sa najviše energije, bio je blokiran od strane Zemljine atmosfere. Ali UVB i UVA posebno, dolazili su neometano. UVB se ispostavilo da je bio jako važan. Veoma je destruktivan. Ali on takođe katalizuje produkciju vitamina D u koži. Vitamin D je molekul koji nam je veoma potreban za naše jake kosti, za zdravlje našeg imunog sistema, i za bezbroj drugih bitnih funkcija u našem telu.
So, living at the equator, we got lots and lots of ultraviolet radiation and the melanin -- this wonderful, complex, ancient polymer compound in our skin -- served as a superb natural sunscreen. This polymer is amazing because it's present in so many different organisms. Melanin, in various forms, has probably been on the Earth a billion years, and has been recruited over and over again by evolution, as often happens. Why change it if it works?
Tako, živeći na ekvatoru, imali smo puno ultravioletne radijacije i melanin, taj predivni, komleksni, antički polimer koji se nalazi u našoj koži, služio nam je kao vrhunska prirodna zaštita od sunca. Taj polimer je zadivljujući jer je prisutan u toliko različitih organizama. Melanin, u različitim formama, verovatno se nalazi na Zemlji milijardu godina. I evolucija ga je iskorišćavala iznova i iznova, kao što se to često dešava. Zašto menjati ako već radi?
So melanin was recruited, in our lineage, and specifically in our earliest ancestors evolving in Africa, to be a natural sunscreen. Where it protected the body against the degradations of ultraviolet radiation, the destruction, or damage to DNA, and the breakdown of a very important molecule called folate, which helps to fuel cell production, and reproduction in the body. So, it's wonderful. We evolved this very protective, wonderful covering of melanin.
Tako je melanin bio korišćen, u našoj vrsti, a posebno u našim najranijim precima koji su evoluirali u Africi, kao prirodna zaštita od sunca. Gde je štitio telo od razarajuće ultravioletne radijacije, od uništenja ili oštećenja DNK, i od razaranja veoma važnog molekula koji se zove folna kiselina, a koja potpomaže produkciju ćelija, i reprodukciju u telu. Tako da je to predivno. Stvoren je ovaj visoko zaštitni, savršeni pokrivač - melanin.
But then we moved. And humans dispersed -- not once, but twice. Major moves, outside of our equatorial homeland, from Africa into other parts of the Old World, and most recently, into the New World. When humans dispersed into these latitudes, what did they face? Conditions were significantly colder, but they were also less intense with respect to the ultraviolet regime.
Ali onda smo se odselili. Ljudi su se raselili, ne jednom, već dva puta. Veliki pokreti, van ekvatorijalnog doma, iz Afrike, u druge delove starog sveta, i skorije, u novi svet. Kada su se ljudi raselili u ove geografske širine, sa čime su se suočili? Uslovi su bili značajno hladniji, ali takođe su bili manje intenzivni u odnosu na ultravioletni režim.
So if we're somewhere in the Northern Hemisphere, look at what's happening to the ultraviolet radiation. We're still getting a dose of UVA. But all of the UVB, or nearly all of it, is dissipated through the thickness of the atmosphere. In the winter, when you are skiing in the Alps, you may experience ultraviolet radiation. But it's all UVA, and, significantly, that UVA has no ability to make vitamin D in your skin.
Tako, ukoliko se nalazimo negde na severnoj hemisferi, pogledajte šta se dešava sa ultravioletnom radijacijom. Mi i dalje dobijamo dozu UVA. Ali sav UVB, ili skoro sav, se raspe kroz atmosferu. Zimi, dok skijate na Alpima, možete iskusiti ultravioletnu radijaciju. Ali to je sve UVA, i što je važno, UVA nema mogućnost da stvara vitamin D u koži.
So people inhabiting northern hemispheric environments were bereft of the potential to make vitamin D in their skin for most of the year. This had tremendous consequences for the evolution of human skin pigmentation. Because what happened, in order to ensure health and well-being, these lineages of people dispersing into the Northern Hemisphere lost their pigmentation. There was natural selection for the evolution of lightly pigmented skin.
Tako su ljudi koji naseljavaju severnu hemisferu, lišeni mogućnosti da proizvode vitamin D u svojoj koži tokom većeg dela godine. Ovo je imalo nesagledive posledice na evoluciju ljudske pigmentacije. Jer šta se desilo, da bi osigurale zdravlje i dobrostanje, ove rase ljudi šireći se prema severnoj hemisferi, izgubile su svoju pigmentaciju. Bila je to prirodna selekcija za evoluciju svetlo pigmentirane kože.
Here we begin to see the evolution of the beautiful sepia rainbow that now characterizes all of humanity. Lightly pigmented skin evolved not just once, not just twice, but probably three times. Not just in modern humans, but in one of our distant unrelated ancestors, the Neanderthals. A remarkable, remarkable testament to the power of evolution. Humans have been on the move for a long time. And just in the last 5,000 years, in increasing rates, over increasing distances. Here are just some of the biggest movements of people, voluntary movements, in the last 5,000 years.
Ovde počinjemo da vidimo evoluciju predivnih sepia tonova koje karakterišu čitavo čovečanstvo. Svetlije pigmentirana koža evoluirala je ne samo jednom, ne dvaput, već verovatno tri puta. Ne samo kod modernih ljudi, već i kod naših dalekih predaka, Neandertalaca. Izuzetan dokaz za moć evolucije. Ljudska vrsta je u pokretu dugo vremena. Samo u poslednjih 5000 godina, u povećanom obimu, na velike distance. Ovo su samo neke od najvećih selidba ljudi, dobrovoljnih, u poslednjih 5000 godina.
Look at some of the major latitudinal transgressions: people from high UV areas going to low UV and vice versa. And not all these moves were voluntary. Between 1520 and 1867, 12 million, 500 people were moved from high UV to low UV areas in the transatlantic slave trade. Now this had all sorts of invidious social consequences. But it also had deleterious health consequences to people.
Pogledajte neke od glavnih migracija po geografskim zonama. Ljudi iz područja sa visokim UV zračenjem idu u predele sa nižim UV zračenjem i obrnuto. Nisu svi ovi pokreti bili dobrovoljni. Između 1520. i 1867. godine, 12 miliona ljudi je preseljeno iz zone visokog UV zračenja u zone niskog UV zračenja, u prekoatlantskoj trgovini robljem. To je vodilo svim vrstama socijalnih posledica. Ali takođe je vodilo i do štetnih posledica na zdravlje ljudi.
So what? We've been on the move. We're so clever we can overcome all of these seeming biological impediments. Well, often we're unaware of the fact that we're living in environments in which our skin is inherently poorly adapted. Some of us with lightly pigmented skin live in high-UV areas. Some of us with darkly pigmented skin live in low-UV areas. These have tremendous consequences for our health.
Pa šta? Bili smo u pokretu. Toliko smo pametni da možemo prevazići sve ove biološke prepreke. Pa ipak, često nismo svesni činjenice da živimo u okruženju u kom je naša koža suštinski loše prilagođena. Neki od nas koji su svetlijeg pigmenta žive u zoni visokog UV zračenja. Neki od nas sa tamnijom kožom žive u zonama nižeg UV zračenja. Ovo ima nesagledive posledice na naše zdravlje.
We have to, if we're lightly pigmented, be careful about the problems of skin cancer, and destruction of folate in our bodies, by lots of sun. Epidemiologists and doctors have been very good about telling us about protecting our skin. What they haven't been so good about instructing people is the problem of darkly pigmented people living in high latitude areas, or working inside all the time.
Mi moramo, ukoliko smo svetlo pigmentirani, da budemo obazrivi kada je u pitanju rak kože, kao i uništenje folne kiseline u telu, od prekomernog sunca. Epidemiolozi i doktori su nam veoma dobro govorili o zaštiti naše kože. Ono u čemu nisu bili tako dobri vezano za informisanje ljudi, jeste problem ljudi koji su tamnije pigmentirani i koji žive u višim geografskim zonama, ili rade u zatvorenom sve vreme.
Because the problem there is just as severe, but it is more sinister, because vitamin D deficiency, from a lack of ultraviolet B radiation, is a major problem. Vitamin D deficiency creeps up on people, and causes all sorts of health problems to their bones, to their gradual decay of their immune systems, or loss of immune function, and probably some problems with their mood and health, their mental health.
Jer su problemi tamo jednako veliki. Ali su mnogo zloćudniji. Jer deficijencija vitamina D, nastala usled manjka ultravioletne B radijacije, je krupan problem. Nedostatak vitamina D se prikrada, i izaziva sve vrste zdravstvenih problema u njihovim kostima, do postepenog razaranja njihovog imunog sistema, ili gubitka imunih funkcija, i verovatno nekih problema sa njihovim raspoloženjem i zdravljem, njihovim mentalnim zdravljem.
So we have, in skin pigmentation, one of these wonderful products of evolution that still has consequences for us today. And the social consequences, as we know, are incredibly profound. We live in a world where we have lightly and darkly pigmented people living next to one another, but often brought into proximity initially as a result of very invidious social interactions. So how can we overcome this? How can we begin to understand it? Evolution helps us.
Tako imamo, u pigmentaciji kože, jedan od divnih proizvoda evolucije, koji i danas ima posledice na nas. A socijalne posledice, kao što znamo, su neverovatno velike. Živimo u svetu u kome svetlo i tamno pigmentirani ljudi žive jedni pored drugih. Ali često su dovedeni u prvobitnu blizinu kao rezultat individualnih socijalnih interakcija. I kako se ovo može prevazići? Kako možemo razumeti ovo? Evolucija nam pomaže.
200 years after Darwin's birthday, we have the first moderately pigmented President of the United States. (Applause) How wonderful is that? (Applause) This man is significant for a whole host of reasons. But we need to think about how he compares, in terms of his pigmentation, to other people on Earth. He, as one of many urban admixed populations, is very emblematic of a mixed parentage, of a mixed pigmentation. And he resembles, very closely, people with moderate levels of pigmentation who live in southern Africa, or Southeast Asia.
200 godina nakon Darvinovog rođenja, imamo prvog umereno pigmentiranog predsednika Amerike. (Aplauz) Koliko je to divno? (Aplauz) Ovaj čovek je značajan zbog mnogo razloga. Ali treba da razmišljamo o tome kako se on poredi, s obzirom na pigmentaciju kože, sa ostalim ljudima na Zemlji. On je, kao jedan iz velikog broja izmešane populacije, simbol mešovitih roditelja, izmešane pigmentacije. I veoma je sličan, veoma blizak, ljudima umerene pigmentacije koji žive u južnoj Africi i jugoistočnoj Aziji.
These people have a tremendous potential to tan, to develop more pigment in their skin, as a result of exposure to sun. They also run the risk of vitamin D deficiency, if they have desk jobs, like that guy. So lets all wish for his great health, and his awareness of his own skin pigmentation.
Ti ljudi imaju ogroman potencijal da tamne, da razvijaju još više pigmenta u svojoj koži, kao rezultat izlaganja suncu. I oni su izloženi povećanom riziku od deficita vitamina D, ukoliko imaju kancelarijske poslove, kao taj čovek. Tako da mu poželimo dobro zdravlje, i svest o sopstvenoj pigmentaciji.
Now what is wonderful about the evolution of human skin pigmentation, and the phenomenon of pigmentation, is that it is the demonstration, the evidence, of evolution by natural selection, right on your body. When people ask you, "What is the evidence for evolution?" You don't have to think about some exotic examples, or fossils. You just have to look at your skin.
Ono što je predivno u vezi sa evolucijom pigmentacije ljudske kože, i fenomenom pigmentacije, jeste to da je to demonstracija, dokaz, evolucije putem prirodne selekcije, upravo na vašem telu. Kada vas ljudi pitaju, "Šta je dokaz evolucije?" ne morate da razmišljate o nekim egzotičnim primerima, ili fosilima. Sve što treba da uradite je da pogledate svoju kožu.
Darwin, I think, would have appreciated this, even though he eschewed the importance of climate on the evolution of pigmentation during his own life. I think, were he able to look at the evidence we have today, he would understand it. He would appreciate it. And most of all, he would teach it.
Mislim da bi Darvin cenio ovo, mada je prevideo važnost klime na evoluciju pigmentacije, tokom svog života. Mislim da bi razumeo, da je samo imao prilike da vidi dokaze kojima raspolažemo danas. Cenio bi to. I najvažnije od svega, poučavao bi.
You, you can teach it. You can touch it. You can understand it. Take it out of this room. Take your skin color, and celebrate it. Spread the word. You have the evolution of the history of our species, part of it, written in your skin. Understand it. Appreciate it. Celebrate it. Go out. Isn't it beautiful? Isn't it wonderful? You are the products of evolution. Thank you. (Applause)
Vi, vi možete poučavati. Možete dotaći. Možete razumeti. Izneti iz ove prostorije. Prihvatite svoju boju kože, i slavite je. Širite priču. Imate evoluciju istorije naše vrste, deo nje, zapisanu na svojoj koži. Razumite to. Cenite. Slavite. Izađite. Zar nije prelepo? Zar nije čudesno? Vi ste produkt evolucije. Hvala vam. (Aplauz)