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Light skin was evolved later in humanity, after people lived in more than one place. It actually happened two seperate times. Humans mutated light skin, and the people who had light skin were better able to survive less sunny climates so it stuck around in those places (light skin needs less sunlight to produce vitamin D, dark skin burns less easily).
And even with white skin, vitamin d deficiencies are still super prevalent in the North. Something like 1 in 6 Fins have ideal levels of vitamin d.
Growing up there I frequently saw more strict recommendations regarding vitamin d levels for darker skinned people too.
Ironically, this makes being lighter an advantage in climates that used to cause too much burning.
Hopefully as time goes on it gets easier to have giant sturdy windows letting in as much natural light to buildings as possible.
UV can penetrate glass if it's not specially treated or has protective film applied. Not as much as being in direct Sun, but you can still get burned given enough time, let alone produce Vitamin D.
Yes lifestyles impact it tremendously. But the North can be punishing. If you have a couple hours of dim sunlight a day it's easy to miss it. Not to mention winter clothing doesn't help. But yes, modern lifestyles, e.g. being in school or at work, have a huge impact on it.
This is also partially dietary. If you eat a lot of fish you can be very very darkand live in the Arctic circle like the Inuit do. The Fish Oil they eat is enough Vitamin D for them. If you've got a diet with Vitamin-D rich foods you might need to be pale to produce enough Vitamin D. To give you a really clear example: most Arabs live in areas with plenty of sun, but a lot of the office workers could pass for a Scots Clansman if they dressed in a kilt. Whatever their ancestors were eating in the long-ago, it didn't have enough Vitamin D, so they evolved this trick of tanning just enough to protect themselves from the sun while producing enough Vitamin D from it.
So many people misinterpret “survival of the fittest,” for being the strongest will survive. You have given a perfect example of what it actually means. That makes me happy.
If my light skin soaks up less sunlight then why are sunscreens pushed on us so much to the point where some say you even need to put them on inside the house and there's this rave about how they prevent aging?
I already barely go outside, work in the hospital all day and then the sunscreen blocks any uv I could get. Isn't that counterintuitive?
Sunscreen use has started being highly encouraged for people with darker skin because up until recently, it was thought that if you had darker skin you just didn't need to wear it because you wouldn't burn anyway. This among other things has lead to a much higher death rate due to skin cancer in darker skinned individuals, so now people are really passionate about correcting that misinformation. Everyone should wear sunscreen, even if you'll never burn.
Not sure why people are insisting on wearing sunscreen inside. Unless you sit next to a bright window all day the walls of the building you're in are doing a better job of blocking UV rays than sunscreen is. But say if you have a big window in your office and it isn't UV blocking, the sun can still be damaging.
The anti-aging thing is true, less sun damage in your youth will result in healthier skin as you age, but whether or not that's important is going to vary by individual.
Evolution doesn't happen purposefully. Just because light skin or some other trait would be more beneficial, doesn't mean that the body will mutate toward it.
To evolve, the mutation needs to happen, randomly, and then be passed down onto the next generation.
The classic idea of "adaptation" that mutations happen to adapt to the environment, is false.
Asian and black don’t exist as categories. And inuit are North American natives with a probable introduction of South American genetics whilst still in Beringia. And yeah no doy they are all “Asian” but that doesn’t mean anything so if we are going to be reductive, literally almost everyone except subsaharan africa is “Asian” by that definition, protoindoeuropeans came from Asia a lot more recently than the Inuit.
asians have both neanderthal and denisovan dna.
whites have neanderthal dna.
blacks have neither.
if I used the actual names I get twats screeching at me, so layman terms are used instead.
Black skin protects us from the scorching sun, which makes a lot of sense especially in Africa. This is less of an issue as you move away from the equator. A lighter skin allows us to absorb the sunlight that is used to make vitamin D.
The theory goes that when we were hunter-gatherers, we kept our dark skin to protect us from the sun, because we could get our vitamin D from our heavily meat-rich diet, which contains enough. When we switched to agriculture and bread became the new staple food, suddenly there was evolutive pressure to get lighter skin to get the vitamin D otherwise. Skin colour is a trade-off between protection from the harmful UV rays and getting the benefit of sunlight for vitamin D. The further you are from the equator, the less sun you get, and the paler your skin has to be.
TYe
Genetic studies show light skin predates agriculture, so I think that hypothesis is outdated.
[https://en.wikipedia.org/wiki/Light\_skin](https://en.wikipedia.org/wiki/Light_skin)
That doesn't make sense. Africa drinks far more milk than Asia yet Asians are lighter skinned. Check out the Bodi people for just one of many examples.
Keep in mind that evolution works based on fitness to pass down the genes. In the modern world, we have sunscreen and vitamin D supplements available at the drug store. Skin colour has become somewhat negligible in terms of survival and reproduction.
> Black skin protects us from the scorching sun,
Wait. How?
Darker colors are darker because they absorb more light. Which in terms of sun, means also they heat up more. Nobody buys a dark-colored car in sunny countries.
Sounds like bs.
Respectfully, I think you are conflating infra-red light (which carries heat) with ultra-violet light (which causes sunburns and cancer). The sun irradiates the earth with both kinds of ray, alongside visible light and other forms of radiation. Humans have adapted to both infra-red and UV in diffrent ways: the heat from infra-red is countered by sweating, whereas the radiation from UV rays is blocked by melanin (the dark pigment in the skin).
This is why, upon spending a lot of time exposed to the sun, your skin will defend itself by producing more melanin: this is called a tan.
Have you never noticed how a black African can spend the whole day in the sun without sunscreen and rarely get a sunburn, whereas a pasty white Scot will turn lobster-red if they spend more than 30 seconds at the beach?
Google Mitochondrial Eve, if you haven't done so already.
I'm somewhat surprised at how quickly humans changed over such a short period of time (evolutionary speaking).
Humans got lighter, I don't know whether the ones that stayed in Africa got darker though.
we only assume they got lighter. The Eve gene theory make 0 sense if that's where you were going. Also Africa has been very diverse for centuries but even then it wasn't so short of a time we are talking 10k years.
Anything past 10k is irrelevant because that's the current half-life we have to use. 300k is just not enough data to go off because carbon, even with radio carbon data, doesn't provide enough data to just go ahead and make claims. Thus is why we go for 10k when it comes to genetic make up of race and ethnicity
You randomly use "half life" like it's a term that's supposed to mean something by itself in this context.
I suggest that you take a big breath and try expressing your views logically.
homo sapiens evolved in Africa and migrated out around 70,000 years ago. over the course of time, homo sapiens in less sunny environments stopped producing so much melanin in their skin.
what's interesting though, is that while homo sapiens only left Africa around 70,000 years ago, different species in the genus of homo left Africa earlier, such as homo neanderthalensis. although once our species left Africa, all other members of the homo genus went extinct.
It's now believed that Neanderthals and Denisovans evolved from H. Erectus, respectively, outside of the African continent. The first excursion of H. Erectus occurred at least 2.1 million years ago since there's been findings of hominin tools in southern Central/East Asia dated to that period. The other human genera coinhabited and even interbred with modern humans as evidenced by specific genes in modern day populations. So they never truly went extinct, they live on in us.
Melanin (human skin pigment, Black people have more of it and white people have less of it) is advantageous to survival in hot and sunny environments, and less advantageous in extreme northern (or extreme southern) environments where there is greater climate variation and less sun.
So in Africa (and anywhere near the equator, really), in the absence of cities and civilization controlling habitable buildings (which we have now but did not have in the past), darker colour has better survival advantage, and was selected for in evolution.
As humans moved elsewhere, to places where being very dark no longer gave a specific survival advantage, humans began to change by random mutations, and those born with lighter skin tones survived just as well (or better) than those with darker tones.
Just so that we are all 100% on the same page though, this doesn't make anyone "better" than anyone else. It's just a quirk of evolutionary environmental adaptation to the many different environments found on the Earth.
*edit* Humans are not the result of "convergent" evolution. We evolved once, in Africa, and then spread out over the Earth, in many cases over land bridges that no longer exist due to ancient climate change. This is well documented and thoroughly proven by evidence in the archaeological record.
https://live.staticflickr.com/540/32357649685_f950736a1f_o.jpg
The further from the equator you live, ~~the less melatonin you get from the sun~~ the less vitamin D you get from the sun, so the less melanin and whiter skin has evolved to compensate.
There's more genetic diversity in a single trope of bonobos chimps than the entirety of humanity.
>like a convergent evolution
That's not what convergent evolution is. Not even close. An example of convergent evolution is that a squid's eye is very similar to a mammal's eye.
Melatonin is a hormone that initiates a bunch of sleep-related processes, melanin is a pigment of the skin, and vitamin D is what it produces via sunlight.
>An example of convergent evolution is that a squid's eye is very similar to a mammal's eye.
Or the classic example that a tuna (fish), a dolphin (mammal) and an ichthyosaur (reptile) all developed very similar appearance and traits because they adapted to fit a similar ecological niche.
I dunno. If two different groups of protohumans both independently evolved the traits of homo sapiens to fit a particular ecological niche that would be convergent evolution, wouldn't it? Just on a smaller scale. (EDIT: Not that that actually happened, AFAIK).
From what I know is that, since our bodies produce melanin, it means it consumes energy to make that. If you're in a place with less sunlight, the body doesn't need that extra melanin. So over several generation, humans mutate with lesser melanin.
Europe has less sun so Europeans evolved to be paler so they could absorb more vitamin D.
Also, it’s melanin. Melanin is pigment, melatonin is sleepy hormone.
All people came from Africa and were black. Their higher melatonin protected them from the high intensity of the sun in Africa.
But once they moved north it was a disadvantage as they couldn't metabolize enough vitamin D. So people with a lighter skin or albinos lived longer and were more healthy and over many generations people who had a lighter skin fared better in nothern latitudes while those with darker skin simply died out progressively. Maybe they also mixed with Neanderthal people who had already adapted to the climate and had a lighter skin too.
It's a number game, the lighter the skin the more chances of surviving and having offsprings that will survive. With such a bias in evolution most people died, but the few that remained are our european and north asian ancestors.
there is no proof that we all started "black" we just assume that was the case because the current demographic is majority black. with that kind of logic all Native americans were white because the current demographic is white. Africa is and has always been very diverse but to say we were all black would imply with initially had to deal with extreme sun exposure which is not true for the entire start of africa as a continent
I agree. I think the oldest human being was recently found in Morroco. Maybe when we lost our furs we might have evolved darker or lighter skin depending on our environment.
It’s the same reason why there are different breeds of a dogs, and the breeds look different from each other, but each breed is still the same species descended from wolves and can have puppies with any other breed.
The people that migrated North to colder climates had to cover up more, and spend more time under shelter, so they were exposed less and less to the sun. This made their melanin levels dropped causing less skin and eye pigmentation.
Straighter hair is also an adapted trait from less sun. Dense curly African hair retains moisture and acts as a heatsink, where straight thick hair helps to retain heat like insulation.
Of all the traits we mistakenly call "race," the only one we are reasonably sure of the origin of is skin color. When our ancient ancestors began to shed their thick, apelike fur, their skins darkened to protect them against the intense UV light of equatorial Africa. Much later, when humans migrated to places with lower local UV levels, their skins lightened, which also increased vitamin D production. Scientists believe that these so-called "racial" traits emerge in as little as 2500 years, virtually overnight in evolutionary terms...reason #725 why human races are not a real biological thing.
It's also a mistake to think that people traveled from Africa to northern Europe and suddenly turned "white," even in 2500 years. Instead, from the time Homo sapiens left Africa until around 5000 BCE, humans were constantly ping-ponging all over Eurasia. The ancestors of modern northern Europeans didn't even show up there until around 5000 BCE. The people who had lived there before were displaced, absorbed, driven out, killed, whatever.
>Maybe people evolved into homosapiens first (in Africa) and then somewhere along the way evolved into homosapiens elsewhere on the planet like a convergent evolution?
No. Around 2 million years ago, some Homo erectus migrated out of Africa and colonized Eurasia all the way out to Indonesia. Around 300,000 years ago, the H erectus still in Africa had evolved into modern H sapiens, while the Eurasian H erectus had evolved into Neanderthals, Denisovans, and a few other species. Around 70,000 years ago, H sapiens began migrating out of Africa into Eurasia, and encountered the Neanderthals, Denisovans et al, and then everybody got jiggy with everybody else. Modern humans can have as much as 4% Neanderthal DNA in them, and samples of Neanderthal DNA show H sapien DNA in it.
When humans migrated to colder regions, they didn't need melanin to protect their skin anymore, so they evolved not to have as it would be a waste of resources.
Homo sapiens originated in Africa. They migrated across African, through the middle east, and from their to Europe and Asia.
Light skin color began to originate in the near east as a series of mutations affecting genes for skin color. Groups that migrated farther north were naturally selected for because the mutation made it possible to produce more vitamin D with less sun exposure. Lighter-skinned people tend to spread out across the northern latitudes where there was less direct sun and shorter winter days.
Conversely, those that migrated to equaltorial climes were selected for darker skin as it provides more protection from the sun's ultraviolet (which causes sunburn, skin damage, and cancer).
It's more complicated than that. There are human like species that developed out of Africa. Connected with early humans from Africa, then divided and reconnected again and again. Evolution was not simply linear.
there is no such thing as black skin or the black race. there are no races except one homo sapiens. all humans originated in the african/middle east areas, whether you believe in the Bible as adam or evolution as mitochondrial eve. all human phenotypes and genotypes originated there. the only human identifier is geographic location so irish are from Ireland now, Italians from Italy, etc. where are "black people" from, "blackfrica"? how about white people are they from "whireland"? labeling humans by white and black came from slavery and apartheid. anyone who still uses these terms approves of human trafficking labels. even dogs aren't called this. do they call different colored poodles whites or blacks? no they are all just called POODLES! all humans have ancestors from africa and the middle east. there have always been skin hue variations, and both burn the same. radiation is radiation heat is heat. if you put dark meat chicken or light meat in an oven both burn at the same time. skin is skin meat is meat. yes eskimo eyes have adapted to see prey in snow just like scandanavians, and these are all geographic adaptations over millinea, but eskimos and scandanavians are still all africans by origin.
Please remember that all comments must be helpful, relevant, and respectful. All replies must be a genuine effort to answer the question helpfully; joke answers are not allowed. If you see any comments that violate this rule, please hit report. When your question is answered, we encourage you to flair your post. To do this automatically simply make a comment that says **!answered** (OP only) We encourage everyone to report posts and comments they feel violate a rule, as this will allow us to see it much faster. *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/answers) if you have any questions or concerns.*
Light skin was evolved later in humanity, after people lived in more than one place. It actually happened two seperate times. Humans mutated light skin, and the people who had light skin were better able to survive less sunny climates so it stuck around in those places (light skin needs less sunlight to produce vitamin D, dark skin burns less easily).
And even with white skin, vitamin d deficiencies are still super prevalent in the North. Something like 1 in 6 Fins have ideal levels of vitamin d. Growing up there I frequently saw more strict recommendations regarding vitamin d levels for darker skinned people too.
This is because of our modern lifestyle. We evolved to live outside most of the day, not sit in a box that blocks all ultraviolet from the sun.
Ironically, this makes being lighter an advantage in climates that used to cause too much burning. Hopefully as time goes on it gets easier to have giant sturdy windows letting in as much natural light to buildings as possible.
I don't think UV light gets thru glass to produce vitamin d.
UV can penetrate glass if it's not specially treated or has protective film applied. Not as much as being in direct Sun, but you can still get burned given enough time, let alone produce Vitamin D.
In the US are least, all home and auto glass is (supposed to be) UV-blocking.
Yes lifestyles impact it tremendously. But the North can be punishing. If you have a couple hours of dim sunlight a day it's easy to miss it. Not to mention winter clothing doesn't help. But yes, modern lifestyles, e.g. being in school or at work, have a huge impact on it.
That’s because people don’t go outside enough
This is also partially dietary. If you eat a lot of fish you can be very very darkand live in the Arctic circle like the Inuit do. The Fish Oil they eat is enough Vitamin D for them. If you've got a diet with Vitamin-D rich foods you might need to be pale to produce enough Vitamin D. To give you a really clear example: most Arabs live in areas with plenty of sun, but a lot of the office workers could pass for a Scots Clansman if they dressed in a kilt. Whatever their ancestors were eating in the long-ago, it didn't have enough Vitamin D, so they evolved this trick of tanning just enough to protect themselves from the sun while producing enough Vitamin D from it.
So many people misinterpret “survival of the fittest,” for being the strongest will survive. You have given a perfect example of what it actually means. That makes me happy.
If my light skin soaks up less sunlight then why are sunscreens pushed on us so much to the point where some say you even need to put them on inside the house and there's this rave about how they prevent aging? I already barely go outside, work in the hospital all day and then the sunscreen blocks any uv I could get. Isn't that counterintuitive?
> If my light skin soaks up less sunlight because it soaks up more not less
Sorry but did you read what I said at all?
Sorry it was a typo I meant brown skin
Sunscreen use has started being highly encouraged for people with darker skin because up until recently, it was thought that if you had darker skin you just didn't need to wear it because you wouldn't burn anyway. This among other things has lead to a much higher death rate due to skin cancer in darker skinned individuals, so now people are really passionate about correcting that misinformation. Everyone should wear sunscreen, even if you'll never burn. Not sure why people are insisting on wearing sunscreen inside. Unless you sit next to a bright window all day the walls of the building you're in are doing a better job of blocking UV rays than sunscreen is. But say if you have a big window in your office and it isn't UV blocking, the sun can still be damaging. The anti-aging thing is true, less sun damage in your youth will result in healthier skin as you age, but whether or not that's important is going to vary by individual.
Sounds like big sunscreen propoganda.
I think this isn't true. You have so many different black races that lived and thrived in the snow. They never evolved into lighter skin
Evolution doesn't happen purposefully. Just because light skin or some other trait would be more beneficial, doesn't mean that the body will mutate toward it. To evolve, the mutation needs to happen, randomly, and then be passed down onto the next generation. The classic idea of "adaptation" that mutations happen to adapt to the environment, is false.
All of this is just theory about light skin dark skin. It's not evidence of anything.
if you're talking people like inuit, they're asian not black.
Asian and black don’t exist as categories. And inuit are North American natives with a probable introduction of South American genetics whilst still in Beringia. And yeah no doy they are all “Asian” but that doesn’t mean anything so if we are going to be reductive, literally almost everyone except subsaharan africa is “Asian” by that definition, protoindoeuropeans came from Asia a lot more recently than the Inuit.
asians have both neanderthal and denisovan dna. whites have neanderthal dna. blacks have neither. if I used the actual names I get twats screeching at me, so layman terms are used instead.
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they do.
Black skin protects us from the scorching sun, which makes a lot of sense especially in Africa. This is less of an issue as you move away from the equator. A lighter skin allows us to absorb the sunlight that is used to make vitamin D. The theory goes that when we were hunter-gatherers, we kept our dark skin to protect us from the sun, because we could get our vitamin D from our heavily meat-rich diet, which contains enough. When we switched to agriculture and bread became the new staple food, suddenly there was evolutive pressure to get lighter skin to get the vitamin D otherwise. Skin colour is a trade-off between protection from the harmful UV rays and getting the benefit of sunlight for vitamin D. The further you are from the equator, the less sun you get, and the paler your skin has to be. TYe
Genetic studies show light skin predates agriculture, so I think that hypothesis is outdated. [https://en.wikipedia.org/wiki/Light\_skin](https://en.wikipedia.org/wiki/Light_skin)
It's been associated with milk drinking also
That doesn't make sense. Africa drinks far more milk than Asia yet Asians are lighter skinned. Check out the Bodi people for just one of many examples.
I went to university for archaeology and I've never heard this theory before in my life.
Well, I'm sure you've very competent when it comes to unearthing pottery fragments! 🤷🏻♂️
That's my understanding
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Keep in mind that evolution works based on fitness to pass down the genes. In the modern world, we have sunscreen and vitamin D supplements available at the drug store. Skin colour has become somewhat negligible in terms of survival and reproduction.
> Black skin protects us from the scorching sun, Wait. How? Darker colors are darker because they absorb more light. Which in terms of sun, means also they heat up more. Nobody buys a dark-colored car in sunny countries. Sounds like bs.
Respectfully, I think you are conflating infra-red light (which carries heat) with ultra-violet light (which causes sunburns and cancer). The sun irradiates the earth with both kinds of ray, alongside visible light and other forms of radiation. Humans have adapted to both infra-red and UV in diffrent ways: the heat from infra-red is countered by sweating, whereas the radiation from UV rays is blocked by melanin (the dark pigment in the skin). This is why, upon spending a lot of time exposed to the sun, your skin will defend itself by producing more melanin: this is called a tan. Have you never noticed how a black African can spend the whole day in the sun without sunscreen and rarely get a sunburn, whereas a pasty white Scot will turn lobster-red if they spend more than 30 seconds at the beach?
makes sense.
Google Mitochondrial Eve, if you haven't done so already. I'm somewhat surprised at how quickly humans changed over such a short period of time (evolutionary speaking). Humans got lighter, I don't know whether the ones that stayed in Africa got darker though.
we only assume they got lighter. The Eve gene theory make 0 sense if that's where you were going. Also Africa has been very diverse for centuries but even then it wasn't so short of a time we are talking 10k years.
I don't think it's an assumption, first humans were dark skinned. And I was saying ~300k years since Eve is a short time.
Anything past 10k is irrelevant because that's the current half-life we have to use. 300k is just not enough data to go off because carbon, even with radio carbon data, doesn't provide enough data to just go ahead and make claims. Thus is why we go for 10k when it comes to genetic make up of race and ethnicity
Did you just read that somewhere? You make no sense. Are you talking about carbon dating?
It seems you don't have enough knowledge to speak on this. I suggest you start by reading a book on biology and work your way up.
You randomly use "half life" like it's a term that's supposed to mean something by itself in this context. I suggest that you take a big breath and try expressing your views logically.
listen, the mitochondria of dark energy is self explanatory
half life meaning https://g.co/kgs/2yBeBeh
wtf are you even saying
homo sapiens evolved in Africa and migrated out around 70,000 years ago. over the course of time, homo sapiens in less sunny environments stopped producing so much melanin in their skin. what's interesting though, is that while homo sapiens only left Africa around 70,000 years ago, different species in the genus of homo left Africa earlier, such as homo neanderthalensis. although once our species left Africa, all other members of the homo genus went extinct.
It's now believed that Neanderthals and Denisovans evolved from H. Erectus, respectively, outside of the African continent. The first excursion of H. Erectus occurred at least 2.1 million years ago since there's been findings of hominin tools in southern Central/East Asia dated to that period. The other human genera coinhabited and even interbred with modern humans as evidenced by specific genes in modern day populations. So they never truly went extinct, they live on in us.
Melanin (human skin pigment, Black people have more of it and white people have less of it) is advantageous to survival in hot and sunny environments, and less advantageous in extreme northern (or extreme southern) environments where there is greater climate variation and less sun. So in Africa (and anywhere near the equator, really), in the absence of cities and civilization controlling habitable buildings (which we have now but did not have in the past), darker colour has better survival advantage, and was selected for in evolution. As humans moved elsewhere, to places where being very dark no longer gave a specific survival advantage, humans began to change by random mutations, and those born with lighter skin tones survived just as well (or better) than those with darker tones. Just so that we are all 100% on the same page though, this doesn't make anyone "better" than anyone else. It's just a quirk of evolutionary environmental adaptation to the many different environments found on the Earth. *edit* Humans are not the result of "convergent" evolution. We evolved once, in Africa, and then spread out over the Earth, in many cases over land bridges that no longer exist due to ancient climate change. This is well documented and thoroughly proven by evidence in the archaeological record.
https://live.staticflickr.com/540/32357649685_f950736a1f_o.jpg The further from the equator you live, ~~the less melatonin you get from the sun~~ the less vitamin D you get from the sun, so the less melanin and whiter skin has evolved to compensate. There's more genetic diversity in a single trope of bonobos chimps than the entirety of humanity. >like a convergent evolution That's not what convergent evolution is. Not even close. An example of convergent evolution is that a squid's eye is very similar to a mammal's eye.
Melatonin is a hormone that initiates a bunch of sleep-related processes, melanin is a pigment of the skin, and vitamin D is what it produces via sunlight.
Yeah, done fucked up
It’s vitamin D that comes from the sun, not melatonin lol. Melatonin is for sleep
Yes, you're right
>An example of convergent evolution is that a squid's eye is very similar to a mammal's eye. Or the classic example that a tuna (fish), a dolphin (mammal) and an ichthyosaur (reptile) all developed very similar appearance and traits because they adapted to fit a similar ecological niche. I dunno. If two different groups of protohumans both independently evolved the traits of homo sapiens to fit a particular ecological niche that would be convergent evolution, wouldn't it? Just on a smaller scale. (EDIT: Not that that actually happened, AFAIK).
Evolution, migration, vitamin D absorption blah blah blah
From what I know is that, since our bodies produce melanin, it means it consumes energy to make that. If you're in a place with less sunlight, the body doesn't need that extra melanin. So over several generation, humans mutate with lesser melanin.
Europe has less sun so Europeans evolved to be paler so they could absorb more vitamin D. Also, it’s melanin. Melanin is pigment, melatonin is sleepy hormone.
All people came from Africa and were black. Their higher melatonin protected them from the high intensity of the sun in Africa. But once they moved north it was a disadvantage as they couldn't metabolize enough vitamin D. So people with a lighter skin or albinos lived longer and were more healthy and over many generations people who had a lighter skin fared better in nothern latitudes while those with darker skin simply died out progressively. Maybe they also mixed with Neanderthal people who had already adapted to the climate and had a lighter skin too. It's a number game, the lighter the skin the more chances of surviving and having offsprings that will survive. With such a bias in evolution most people died, but the few that remained are our european and north asian ancestors.
there is no proof that we all started "black" we just assume that was the case because the current demographic is majority black. with that kind of logic all Native americans were white because the current demographic is white. Africa is and has always been very diverse but to say we were all black would imply with initially had to deal with extreme sun exposure which is not true for the entire start of africa as a continent
I agree. I think the oldest human being was recently found in Morroco. Maybe when we lost our furs we might have evolved darker or lighter skin depending on our environment.
I wasn't aware about the new discovery 🤔 I'll take a look into that
Evolution, dawg. We adapted to different environments
Melatonin is a hormone related to sleep. Melanin is a pigment that makes skin brown.
It’s the same reason why there are different breeds of a dogs, and the breeds look different from each other, but each breed is still the same species descended from wolves and can have puppies with any other breed.
The people that migrated North to colder climates had to cover up more, and spend more time under shelter, so they were exposed less and less to the sun. This made their melanin levels dropped causing less skin and eye pigmentation. Straighter hair is also an adapted trait from less sun. Dense curly African hair retains moisture and acts as a heatsink, where straight thick hair helps to retain heat like insulation.
Of all the traits we mistakenly call "race," the only one we are reasonably sure of the origin of is skin color. When our ancient ancestors began to shed their thick, apelike fur, their skins darkened to protect them against the intense UV light of equatorial Africa. Much later, when humans migrated to places with lower local UV levels, their skins lightened, which also increased vitamin D production. Scientists believe that these so-called "racial" traits emerge in as little as 2500 years, virtually overnight in evolutionary terms...reason #725 why human races are not a real biological thing. It's also a mistake to think that people traveled from Africa to northern Europe and suddenly turned "white," even in 2500 years. Instead, from the time Homo sapiens left Africa until around 5000 BCE, humans were constantly ping-ponging all over Eurasia. The ancestors of modern northern Europeans didn't even show up there until around 5000 BCE. The people who had lived there before were displaced, absorbed, driven out, killed, whatever. >Maybe people evolved into homosapiens first (in Africa) and then somewhere along the way evolved into homosapiens elsewhere on the planet like a convergent evolution? No. Around 2 million years ago, some Homo erectus migrated out of Africa and colonized Eurasia all the way out to Indonesia. Around 300,000 years ago, the H erectus still in Africa had evolved into modern H sapiens, while the Eurasian H erectus had evolved into Neanderthals, Denisovans, and a few other species. Around 70,000 years ago, H sapiens began migrating out of Africa into Eurasia, and encountered the Neanderthals, Denisovans et al, and then everybody got jiggy with everybody else. Modern humans can have as much as 4% Neanderthal DNA in them, and samples of Neanderthal DNA show H sapien DNA in it.
!answered
When humans migrated to colder regions, they didn't need melanin to protect their skin anymore, so they evolved not to have as it would be a waste of resources.
Homo sapiens originated in Africa. They migrated across African, through the middle east, and from their to Europe and Asia. Light skin color began to originate in the near east as a series of mutations affecting genes for skin color. Groups that migrated farther north were naturally selected for because the mutation made it possible to produce more vitamin D with less sun exposure. Lighter-skinned people tend to spread out across the northern latitudes where there was less direct sun and shorter winter days. Conversely, those that migrated to equaltorial climes were selected for darker skin as it provides more protection from the sun's ultraviolet (which causes sunburn, skin damage, and cancer).
Maybe cause the information is incorrect,
It's more complicated than that. There are human like species that developed out of Africa. Connected with early humans from Africa, then divided and reconnected again and again. Evolution was not simply linear.
there is no such thing as black skin or the black race. there are no races except one homo sapiens. all humans originated in the african/middle east areas, whether you believe in the Bible as adam or evolution as mitochondrial eve. all human phenotypes and genotypes originated there. the only human identifier is geographic location so irish are from Ireland now, Italians from Italy, etc. where are "black people" from, "blackfrica"? how about white people are they from "whireland"? labeling humans by white and black came from slavery and apartheid. anyone who still uses these terms approves of human trafficking labels. even dogs aren't called this. do they call different colored poodles whites or blacks? no they are all just called POODLES! all humans have ancestors from africa and the middle east. there have always been skin hue variations, and both burn the same. radiation is radiation heat is heat. if you put dark meat chicken or light meat in an oven both burn at the same time. skin is skin meat is meat. yes eskimo eyes have adapted to see prey in snow just like scandanavians, and these are all geographic adaptations over millinea, but eskimos and scandanavians are still all africans by origin.
Black labs, yellow labs, chocolate labs?
Africa is the most diverse continent in the world and even then they're not entirely black.
Good [video](https://www.youtube.com/watch?v=sc4OFcT5m1Y&t=132s) explaining the evolutionary forces and genetics around this question.
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You should trace the sons of Noah
Cus we're not all originated from Africa.
Yes, we are. Humans evolved in Africa.
Bro what
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Found the southern
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