Nina Jablonski breaks the illusion of skin color
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- čas přidán 6. 08. 2009
- www.ted.com Nina Jablonski says that differing skin colors are simply our bodies' adaptation to varied climates and levels of UV exposure. Charles Darwin disagreed with this theory, but she explains, that's because he did not have access to NASA.
TEDTalks is a daily video podcast of the best talks and performances from the TED Conference, where the world's leading thinkers and doers give the talk of their lives in 18 minutes. Featured speakers have included Al Gore on climate change, Philippe Starck on design, Jill Bolte Taylor on observing her own stroke, Nicholas Negroponte on One Laptop per Child, Jane Goodall on chimpanzees, Bill Gates on malaria and mosquitoes, Pattie Maes on the "Sixth Sense" wearable tech, and "Lost" producer JJ Abrams on the allure of mystery. TED stands for Technology, Entertainment, Design, and TEDTalks cover these topics as well as science, business, development and the arts. Closed captions and translated subtitles in a variety of languages are now available on TED.com, at www.ted.com/translate. Watch a highlight reel of the Top 10 TEDTalks at www.ted.com/index.php/talks/top10 - Věda a technologie
I wish all women and those men in the Philippines OBSESSED with whitening products and lightening their skins can see this video.
+serenity0324 yeahh.
+serenity0324 I'm not sure they would see the relevance I don't know why a beautiful or ugly person for that matter want to change their skin colour but evolution probably isn't high on the list
+serenity0324 Thats because we live in a Eurocentric point of view were everything associated with white is good and everything associated with black is bad.
Yeah I'm sure this one video would change their entire culture, you colonist oppressor,let them practice their culture freely instead of imposing you colonial white privilege on them.
serenity0324 - It won't help its to deep in the culture
Child if they would have taught me THIS type of stuff in school I probably would have been a scientist already. This is amazing
science came from human curiosity, so if you have the ability to be curious, you are a scientist.
@@TheIsaacShin Fallacy of affirmation of the consequent.
@@JimBalter Would that be towards the person's comment I replied to? Or my response to her statement? Or both?
Either way, thank you.
@@JimBalter I thought about it for 2 more seconds. You are absolutely correct, if she knew her statement was Fallacy of affirmation of the consequent, she would not have made it. I think this was her way of complimenting the video & the speaker.
@@TheIsaacShin It was your statement that was fallacious ... scientists are curious, but curious people aren't necessarily scientists.
Why oh why isn't this part of the school curriculum? 😳 It would have made my life so much easier!
The sun teaches this harsh lesson to us whities every time we go outside in the summer: "Respect me or i will burn you" Even in cold climates our skin is so poorly equiped to block UV rays, that just 30 minutes of exposure can cause your skin to redden, Peal and fall off, as if you had poured boiling water over yourself. In the worst cases it causes skin cancer.
I don't know. So please, become a teacher and make the change! :)
@@Ummmmwtf............. same :)
you can't teach this and perpetuate institutional racism; you'd have to change history books; since light skin is a relatively recent phenomena. We teach social constructs like race..and white and black versus ethnicity.
funny this is part of my AP Human Geography course
Jablonski is so brilliant and passionate, as well as kind and generous in person. I used knew her when she lived in the Bay Area, lost touch when she moved back east. She's fascinating to listen to, in person and in public.
She says 1 1/2 -2 m years ago, but I read that it's possible that Europeans weren't white until as late as 10,000 years ago
Yes, she says we were all dark pigmented ~2 m yrs ago not that we diversified our skin tones at that time.
I know this is 5 yrs after the comment but still wanted to respond for future viewers.
I think she was just highlighting when humans actually moved to colder lands. It would have taken much much longer for lighter skin to become the norm in those places - i.e. only 10,000 years ago
I use to teach diversity and wellness, with emphasis on resilience and skin evolution, to a very diverse group of at risk youth at Job Corps in SF and by the end of the session some kids actually cried about the good feeling and understanding the information gave.
That’s incredible ❤
This made me want to go sit in the sun for a bit
I wish my fellow Filipinos will be soon proud of their natural tan skin
White skin has little pigment to make the most of UVB rays during the very short northern summer. (you must use UVB sunscreen during summer in Europe )The closer you get to the equator, the more UVB you get till it is constant year round. The maps she showed, proved the intensity of UVB is also varied in the equatorial regions, and corresponds to the different "tones" of our relatives even in this region.
Wow! Thank you for this wonderful video!!!
Is there any kind of skin treatment available to change complexion genetically? Mam?
I suppose that those who were left confused simply don't understand the theory of evolution via natural selection. I highly suggest reading up on these two topics and watching this video again.
In a nutshell, she is saying that people with darker skin pigmentation survived better in areas with higher UV radiation leaving them more chances to reproduce offspring. And vice versa for the lighter skin pigmentation in areas with lower UV radiation.
Yes I agree. Our skin colors don't depend on the position of where our country is located in the world but it is our adaptation to different climates and the levels of exposure in a specific place.
This is 100% true. White people get harsh sunburns unlike darker skin tones.
Yeah they have skin tones for cold environment s.
🔥
@@user-lu6yg3vk9z White people are not cold adapted at all they burn in the winter and their skin reflects sunlight which is why they fortify their foods and have low bone density genetic fitness and suffer from folate depletion. All the most Northern populations are all dark skinned. White people are albinos spawned from albino Indians during a plague event in India 6500-4000 years ago. The exact same mutations responsible for albinism are the same mutations responsible for Eurasian light skin (SLC45A2, SLC24A5, HERC2, OCA2, TYRP1, etc). 98%-100% of Europeans carry A111T, the mutation responsible for Albinos. East Asians have the same melanoma rates as Africans despite being light skinned.
Europeans are albinos.
Science is awesome...
Alex Moen very awesome
Yes it's true even with animals they adapt to their surroundings over time we are NO different than the Bears and the birds around the world that adapt to their climate for protection and survival but people have been knowing this for the longest time and still keep us divided.. there's a ever lasting war against good and evil and the plane is set for destruction in jealousy to take the focus off of something else? The gifts we all have in Enlightenment because knowledge is true power its nothing to do with these illusions that we are constantly programmed to indulge in. We need growth spiritually not physically
very well said :)
Coless Catchings but the plants and animals disn't go pail... This Story has holes
Not Spiritually because that word doesn’t mean anything but I agree with you otherwise
Authentic Makeup Spiritually means it’s coming from God or his words which is written in the Bible.
She failed to mention that melanin is the key component that gives our skin any color at all. When you see a person with light skin, it's because they have substantially less melanin that than of a person with a darker tone.
An example is a good friend of mine, compared to myself. She's basically a walking whiteboard, whereas I have an olive complexion.
Five minutes out in the sun, and she burns. I don't. I have more melanin than her.
In fact, I don't even think the girl has any at all. XD
Her longer presentations provide that information… I imagine it was the sort of basic knowledge she thought most, who would be attending a Ted Talk, would know.
Theres this thing we do called wearing clothing and living in a shelter people. Some folk refuse to even go outside nowadays so it stands to reason how the evolution in skin coloring has slowed to a minimal not mention as she stated we can move anywhere at a moments notice instead of staying stagnant in the same regions...
There are huge holes. The colour coded atlas for example showed new Zealand as light in shade. That's European migration. The original people where brown
The original people didn't arrive that many years ago and actually came from the Polynesian Islands which are closer to the Equator
@@shaolinshifu1
Now I want to know how many generations does it take for people to change pigmentation so much we can tell they are either beige, light brown, or dark brown.
As far as I know scientists used to say humans arrived on Europe about 35,000-40,000 yrs ago but new data suggests 210,000 yrs.
I'm not sure if these were different migration waves but supposedly light skin evolved around 15,000 yrs ago.
200,000 yrs or 16,000 yrs living as dark skinned Europeans?
Though Jablonski is (drastically) oversimplifying, the association between endogenous Vitamin D and melanin is definitive and uncontroversial (you can see this yourself by getting a tan). UV exposure is compounded by surface reflection of treeless permafrost in arctic biomes; this is similar to the effect of handheld reflectors used by sunbathers. Coping with the intensity of solar radiation, the Inuit developed special eyewear, without which snowblindness would be endemic.
My high school history teacher (back in the late 80s) told us this story, but did not mention Darwin.
There's no reason to mention him, especially since he got the facts wrong about skin color. The facts are what matters, not whose name is attached to them.
Answering your 2nd question, someone with darker skin needs more UVB light to produce the same amount of vitamin D that someone with lighter skin can in the same conditions.
in polar areas the sun does not shine enough for africans. they need a winter sun holiday wearing a tiny bikini or trunks to absorb those wavelengths of light right onto their eu-melanin containing epidermis to convert cholesterol to vitamin D. the rest is history. 2. sunlight exposure gives ~ 20,000 IUs of vitamin D - the bodies immune system regulator. No food stuffs or supplements come anywhere near the vitamin D that can be produced by the rays of the sun. over exposure to the suns rays causes melanoma in lighter skin. responded to above.
@Goeeegi I don't get how she says they have a potential to tan but then because their skin is brown or black they are at risk of vitamin D deficiency.
But I maintain that she her expertise in biological anthropology is not a degree in medicine and therefore she should never say that blacks are ill-suited for indoor jobs ("desk" jobs) just because of their skin color.
Her tenure does not protect her from termination for irresponsible statements made outside her area of expertise.
Ok, the pigment aspect is becoming apparent but I am curious about variations in hair type.
I am so thankful I am green, I can live anywhere. =)
Yes, I prefer the term used in Star Trek Enterprise : "Pink Skin" much more accurate !
Well, you could easily surmize that if it is hot enough to morph skin, then our noses and mouths would have to adapt to the heat.
Bigger nostrils=Better cooling
Bigger lips=A condition that comes about after long amounts of time in the sun.
Course and Oily Hair=Scalps own way of protecting itself.
So if "everyone" already knew this, why then do people of certain ethnicities react poorly or in disbelief that the original people of Earth were Dark skinned or Black. That fact obviously doesn't make anyone superiro to anyone else but it is a truth that should be taught in pre-college schools so that maybe we would all try to love each other more if we all knew for certain that we were from the same people.....just a thought
Great video! Sadly this is still only a fraction of what they should’ve taught in school 💯
I am truly surprised people didn’t know this. Why did you guys think people have different colors?? 😭 it’s literally common sense
White people are albinos spawned from albino Indians during a plague event in India 6500-4000 years ago. The exact same mutations responsible for albinism are the same mutations responsible for Eurasian light skin (SLC45A2, SLC24A5, HERC2, OCA2, TYRP1, etc). 98%-100% of Europeans carry A111T, the mutation responsible for Albinos. East Asians have the same melanoma rates as Africans despite being light skinned.
Europeans are albinos.
She wasn't saying that melanin is made from the sun...Lol. Pay attention. She's saying that areas with more UV rays make the body react to protect the skin by producing more melanin.
To make it more simple, imagine growing two plants and giving them different amounts of sunlight. Surely, the one receiving the most amount of sunlight will grow healthily and more abundantly.
@chairde the movement of humans from Africa to Europe is much older than the move of humans from Africa to Asia to the Arctic Circle. This information can be found at National Geographic's Human Genome Project, or conversely do a goolge image search of "map of human migration"
I found this to be an incredibly interesting video.
8:58 nice arm placement....
Right lol, when I seen it immediately I had the same exact thought... now I’m wondering who lined his facial hair up so well 🤔
Brilliant talk.
@wmhoad care to back up your opinion with some specific science papers or research?
what about the eskimos?
2 potential factors: one being that the snow amplifies UVR exposure, the other being that they had a seafood diet that consisted of high vitamin D
great documentary.
What country isthe lighter woma from in the split picture with the black woman. She had a tattoo between her eyes
Very interesting video!
@neurel111 I feel like I need to start paying more attention to that vitamins D.
Something that is always glossed over, in my experience, when people make claims about skin colour being an adaptation to levels of solar radiation is that aboriginal Tasmanians experienced similar levels of solar radiation to Europeans, but remained very dark-skinned. I have yet to hear any adaptation-based explanation for that.
The answer is TIME: the region of the planet you refer to was the most recent place we humans came to populate...it takes many 1000’s of years for this change to occur. (Hope this is helpful)
@@madyjules Humans reached Tasmania at least 30,000 years ago. It certainly isn't the most recently populated region. Much of the Pacific region was only populated within the last couple of millennia.
I have a question: with regards to levels of melanin in your skin tone, there are families whose siblings have lower level of melanin and other siblings do not. No mixing. I'm well aware of genetic variation and chromosom crossovers, but how does climate account for this?
I imagine you think there’s no mixing and mixing of who exactly. I don’t have DNA from my father and brother (both deceased) to test this out but based on my XX chromosomes I’m 100% Irish British Isles. I suspect the Y chromosomes in my family tell a different tale. My mother and I were both very white but even she tanned more than me (I barely colour or don’t colour) and she was 100% Irish. My father and brother both got incredibly dark in the sun and my father had olive skin. Whomever gave him those Y genes likely gave them to him a long time ago given what I know about his family’s history.
Although many different species of Homo evolved in different parts of the world, the species Homo Sapien is only known to have evolved in one area, Africa, some 250,000 years ago. The first migration of Homo Sapiens occurred some 150,000 years later into the Levant region (modern day Israel, Lebanon, Jordan, Syria). The next major migration happened about 30,000 years after that and continued intermittantly until the current human distribution you see today.
I can't believe they actually have to put up a VIDEO about this since people don't know about it.
How can you NOT know about this already? It completely blows my mind, honestly! In the schools in my country, we already learn about this and evolution already in the 7th grade.
Bakfifflaren- We all learn an abridged version of this theory over here in the states during 7th grade science class. They continue to emphasize the theory on platforms like this, however, because the illogical racist notions of many people in our country continue to persist. The hope is that this information will positively impact that.
Exactly.
That’s because it’s not entirely true that places close to the equator have darker people. If you look at the UV map, yes the purple and red areas cover most of Africa, but it’s mostly lower UV and blue at the equator in South America. So, people living there are actually moderately pigmented, not dark like in central Africa. So Darwin was right that climate does not affect skin color. He probably noticed some people with darker skin who lived farther from the equator than some people with lighter skin closer to the equator.
Loved the speech!
Thank you very much.
Some people are getting mixed up between skin colour and economic and social advantage. Religion and cultural values have held some people back from advancements. Wars and the need to innovate has pushed technology forward whilst the middle east due to religious dogma has held it back from advancement.
Interesting... explains why I get lighter in the Winter months and darker in the Summer months.
"Fairer"? Dear brother, let's not associate "fairness" with "lighter" skin tone/complexion
This is amazing 🤯
Okay this may be part of the story, but not the entire story, at what point do extraterrestrials come in, and mix their DNA in the species that was current at that time or the multiple times, and the multiple groups that have come, and left, and what effect did that have? Also, the shape of the planet has not always been the same, how do we truly know who is the first species to come to Earth, and what their migration was like? Maybe multiple continents were seeded all at once, throughout the planet, and the level of sunlight in each location affected skin tone as explained, this is also a possibility. To my understanding the first beings to come here were not even humanoid, it seems modern humans are not even the original species of this planet, or entirely of this planet. Earth's history is very convoluted, there is still so much to understand, and learn of our origins. The sunlight part makes sense, in the winter my skin tone gets lighter, and in the summer it gets darker, and the sun is very nourishing but after a certain point it becomes damaging, so it has a dual effect the same way oxygen sustains, and terminates life. Interesting, but incomplete, still much more to know.
@andid Valiant effort talking to Tater. You rock!!
Find Okoye Ahmose and John Ayer's comments, they're ridiculous
reading the title, i thought i was going to watch some stellar magic trick. i am dissapointed
@starlette098 Is this about two parents of a darker tone having a child of a lighter tone, or the tone of either parent? I've never seen that happen.
@wmhoad The 1992 paper was before the HGP findings and even admits "race" is just a concept. On issues of "race" the scientists can be affected either way, it's unfortunate that so many scientists were brought up with an ingrained belief in the existence of biological "race" that few are willing to look for disproof of the concept. .It is usually those who have gained most from a concept (such as "race") and have the most to lose from dropping the concept that fight for the concept the hardest.
Skin pigmentation has nothing to do with where one reside, it's in the gene mutation which produces albinos type 1 and 2.
over 1000s of years of mutation. Been in SA for decades but still the same. LMAO!
White people don’t want to believe that they are the result of albinism. It’s easier for them to believe they evolved.
@@hugojimenez3324 delusion, that's why they believe that they are a different race but the truth is there is one human race.
I don’t think she got enough applause.
@ payarkaaloo . .,...' cause she spoke lies and the audience knew that ....
What about Eskimos? Are they not moderately pigmented?
They also have a vitamin D rich diet, and studies show they synthesize it better if I remember correctly. So no need for lighter skin.
Brilliant!!!
when she said "we moved" she meant it literally. changing the natural habitat, that is.
too bad for you, not everyone is racist.
"hitler would've loved this lecture."
That is totally ridiculous.
What could possibly be twisted about understanding human origins and evolution. People vary, no big deal.
You would prefer to deny reality than deal with it rationally?
We are one planet.
This talk reminds the most forgetful of us of that fact. For that, it was an awesome talk.
Gene flow does not always reduce genetic diversity. In the grand scheme, mobility & speciation interplay with environmental changes & adaptation that are time-sensitive. We'll certainly go extinct as a species, maybe by evolution & not by self-immolation. The question remains about our evolution, which is admittedly a complex crap-shoot; that's why I suggest that geneticists study the impact of rapid climate change on our genetic heirs.
Climate change is certainly bringing out LOTS of CMEs.
This is not a credible hypothesis. In order for skin color to be an evolutionary development people would have to have a survival advantage based on their skin color. Lighter color children would die in areas where dark skinned people thrive. Dark skinned children would die where lighter skinned people survive.
There is a psychological bias in my opinion a sociobiological predisposition, in people to associate with people who have a similar appearance. We see this when sub-cultures focus on identifying themselves with appearance.
I think what probably happened is that people pushed away people with dis-similar appearance. Most people are brown, some are black and some are white. We find regions populated with similar appearing people. The lightest skinned people were aggressively pushed out of Africa and then out of Asia, into Europe.
If skin color provided an evolutionary advantage we would see black children dying in Europe and white children dying in Africa.
Arctic people have lived in the area over 50K years, and they are brown. Skin color does not offer an evolutionary advantage based on geographical location.
Great observation!!
+Okoye Ahmose Thanks.
Brown people living in the artic region survived by getting their vitamin D through oily fish...so there goes your argument.
+Average Joe Nope, no where near. Kind of funny for you to say that. Evolutionary advantage, natural selection, means surviving to reproduce. If black people are more likely to survive in high UV regions then they would die in low UV regions. If white people are less likely to survive to reproduce in high UV areas then we would see them die in high UV regions. Brown people in the arctic and brown people at the equator are just examples of skin tone which is not, as you point out, influenced by natural selection caused by UV radiation. If skin color were naturally selected then people in the arctic who are lighter skinned would be more likely to survive and after 50K years we would see skin color as light as Europe. Your assertion that Brown people above the arctic circle are not naturally selected based on skin tone and UV actually agrees with my point that skin tone is not naturally selected and disagrees with Dr. Jablonski's assertion that skin tone is based on natural selection from UV radiation.
+Average Joe
www.npr.org/sections/health-shots/2013/11/20/246393329/how-a-vitamin-d-test-misdiagnosed-african-americans
There is a difference between races. This is obvious. Trying to prove otherwise just proves your denial. It's not something to get upset about.
Not denial, just science, it's you who deny the truth.
There are even numbers and a definition to prove it.
If you want to build a race, you must have a gene exclusive to your group that you can not pass, and this is not the case for humanity because we have not had time to diversify enough for it.
Moreover, if you want numbers, it takes 2000 years to a group of 100 humans isolated to constitute a race.
Knowing that the majority of human groups necessarily gathered more than 1,000 to 10,000 individuals, it would have taken 200,000 to 2,000,000 years to form races, which is clearly more than the age of modern man. So no races. Just prejudices from our biased vision.
This was really beautiful!
Ok this makes perfectly sense (melanin reduces production of Vitamin D --> human with less melanin are "fitter"). I don't think she said it that way, though.
I think I got it then. The amount of UVB directly correlates to the amount of melanin that is in the skin of fit humans.
Sorry, I do not worship a man who was raised in the illuminati occult. I worship God and his holy book which says that God created many races so that there would be diversity, and with diversity people would recognize and learn from each other, not to rival each other. Also, Inuits and Eskimos who lived very close to the North Pole for thousands of years have brown skin, brown eyes and black hair. Berbers who lived in Northern Africa for thousands of years originally look white and still do.
Look at the migratory movements of men since the beginning of humanity and you will understand better the distribution of the colors of the skin.
Oh how I love confused propaganda.
The assumption that more recent expansions are all driven by cultural factors is based on the notion that modern humans everywhere have essentially the same abilities.
That's a logical consequence of human evolutionary stasis: If humans have not undergone a significant amount of biological change since the expansion out of Africa, then people everywhere would have essentially the same potentials, and no group would have a biological advantage over it's neighbors. But as we never tire of pointing out, there has been significant biological change during that period--tremendous amounts of change, particularly in those populations that have practiced agriculture for a long time.
Therefor, the biological equality of human races and ethnic groups is not inevitable: In fact it's about as likely as a fistful of silver dollars all landing on edge when dropped.
see: 10,000 year explosion
you are as ignorant as piss.
I think what Darwin meant was that skin colour had a genetic component - and was not merely a product of environmental forces. Darwin mentions "three centuries" - which we now know is hardly enough time for adaptations to arise.
Her theory makes absolutely no sense. If her assertion is true then why do you see people who live along the equator with different skin colors? They should all be jet black unless they have some magical cut off switch that makes some have light skin, some with brown skin, some with dark brown skin and some with jet black skin. If her theory is true then how do you explain white people living in S. Africa and their skin not turning dark? How do you explain black people living in England and their skin not turning light? No mention of oculocutaneous type I and II albinism?
The change in skin color, achieved through natural selection, would take thousands of years to happen... Are you sure you should be watching TED Talks?
Not necessarily if you study albinism.
The reason is that we now have lots of shelter, vitamins, and sunblock. We no longer need to evolve in favor of one type of skin tone vs. another. Humans have no natural selection pressures to do so. As far as albinism goes, that is an exception, a congenital disorder.
You would make a terrible scholar because your mind is already made up. Shelter and sunblock are the only support you have? If human skin color miraculously changed thousands of years ago, then that same phenomenon should be occurring today. You should see dark skin people living in northern Europe skin turning lighter or white people who live in S. Africa skin turning darker and producing darker offspring. How do you explain blonde hair and blue eyes then? Did the sun or lack of it change eyes and hair color also? No it didn't. Blonde hair and blue eyes are characteristics of recessive genes. Recessive genes have to come from dominant genes. Any human geneticist will tell you that. Again study albinism in particular oculocutaneous type 1 and 2.
migration
so overly dramatic
You are right. The difference in (average) intelligence between dark and light skinned people is not due to vitamin deficiency, but due to evolution and the drastic differences in our geographies. The harsh cold conditions of E. Asia and Europe encouraged different traits than those observed in darker people. Please see: "Race is More than Skin Color!" video.
You can’t prove what you’re saying about average intelligence because it isn’t true.
Amazing video.
"this theory can not account for other physical characteristics"
Are you saying evolution is wrong?!
i hav nothing to be bitter about when nature is on my side
very interesting
I have a question I'll appreciated if someone responds.
Q: So people with darker skin won't have to use sun screen lotion since they all ready have it naturally in their skin?
If they expose themselves to extreme sunshine over an extended period of time, they will eventually need lotion too. But the effects of UV rays on their skin will usually be less damaging and slower than on light skins.
Nick Pop wrong sun screen lotion is a modern creation for non - melanated beings only
@@blunow5855 I have actually seen blacks use sunscreen.
@@macinhorstemeyer1961 Yes, some do. Lack of knowledge !!!
Evolution is beautiful. One of the most beautiful things. Think about that we all humans have same black "Eve" and "Adam" who once were living there in Africa. We are all African.
10:43 oh crap
What Nina Jablonski fails to mention is that and earlier cro-magnon skeleton was found in South Africa, near the southern polar end.
Respect for your answer, TheGallows32.
Have a nice day : )
Most estimates put genetic variation between random people of the same geographic area at around .1-.5% and the differences between two geographically separate groups at .15%. It is possible to be genetically closer to someone of a different continent than someone down the street. The question, though, is whether or not the variations happen in functional genes (1% of genes are thought to be functional) and if the percentage of "functional" variation is higher between groups than in neighbors.
Thank you!
@Mishkafofer If skin is too dark, it blocks Vitamin D. Low UV means that folate will not be stimulated. Folate is needed for cells to grow and reproduce- they are the stimulant for melanin. Skin color is polygenic, so if UV rays are too low, no stimulation, and eventually (some of) the genes for dark skin shuts off. It's not a "negative effect", just a biological response.
how long does it take to go from black black to white white and visa versa ?
a 1000 years ?
i was thinking about this lately
say you have 100% black (or white) with 100% white (or vis versa)
then your child be 50% black or white
then the next is 25%
the next 12.5%
and so on
after 4 generations you would be pretty much be completly Black or White or whatever
thats less then 100 years
Going from black to white about 16 generations.
About 20,000 years or 4000 generations.
Your question is actually reasonable. Read about Darwin's Finches to understand how evolutionary pressure works on existing genetic mutations.
The answer is "several generations". The exact number of generations, if skin for were selected for by evolution, would be based on a number of variables.
Study Mendel's peas to get an understanding of the math behind evolutionary pressure.
How many members of the community have the selected for mutation, how rapidly do they breed, what are the evolutionary pressures selecting for the existing mutation, etc, etc.
4:43 ?
I didnt think this was news. And Darwin was not wrong. Climate is not UV radiation (maybe you could say that in the modern era, it is part of the climate). Climate is humidity, atmospheric pressure, wind, rainfall, temperature, etc. You can clearly see from her charts that there are places that are cold (like the Andes) that have dark skin pigmentation. Im sure if Darwin understood UV radiation (it was not well understood at that time) he would have put 2 and 2 together.
Where is the ecuador
If you look a the chart in 3:15, you can see that the theory accounts for africans having the darkest skin, south americans (near ecuator) having brown skin, native north americans pale brown, and europeans and asians being white.
The evolutionary tendency to tan would be likely to stay for many generations, even after migrating. So the migration from africa to europe and asia may account for their early tendency to have dark skin.
Climate and the availablity of resources plays a large role in a people's ability to create and sustain modern stuctures of society and technology. Places that contain people that you may term as "lower" are simply living in less forgiving or nuturing location. Has very little to nothing to do about differences in intelegence which are insignificantly small or non existant.
@chuckfaststrat
Is it that I "don't know" what I'm talking about, or is it that you are unable to see things from a different perspective?
Lack of melanin pigmentation is not a mutation. Black populations in central africa have always had variations in pigment producing genes as long as homosapiens have existed. These are kept at current levels due to the advantages that having black skin offers in hot climates. These advantages are reduced in colder the climates and increased in hot ones and so the ratios rebalance favouring lighter or darker skin according to local conditions. Mutation has little part in multi-cellular evolution.
That's because the natives that live in northern Canada have move there recently and mostly likely came from southeast Asia, as you can see on their facial features.
Skin color is not the only difference between the peoples of the world. Just because people refer to ethnicities by skin color doesn't mean they aren't considering the different skeletal structures, skull shapes, facial features, heritages, cultures, ancestry, etc. when they differentiate between peoples. Skin color is used as an identifier, but it's far from being the sole consideration.
EXACTLY....like, the DIFFERENCES between prokaryote and eukaryote CELLS....DNA... 🤷🏽
I agree
This may seem common sense to some, but you would not believe how many people in our day and age still believe that some ghost in the sky created people in different colors and the "fact" that they are lighter gives them authority and superiority over others.
The distinction being made is not actually centered around ethnicity, but rather discusses privileged vs underprivileged.
The dynamics of discrimination are well understood by the social sciences. Colored people are on average are less privileged than whites are, and women are on average less privileged than men are. That makes minority/colored women the most vulnerable members of society. Progressive policy will logically reflect that, as it seeks to uplift the disadvantaged.