Politically incorrect Q: If different racial charactistics evolved as response to different climates, why aren't Alaskan natives or oriental peoples from the north or indigineous peoples of Australia and South Africa as pale as northern Europeans?

According to this article, it has to do with dietary differences. People with diets high in vitamin D don’t need the sun to help them synthesize it. That’s the explanation offered for the Inuit, at least. I don’t know how broadly it might apply.

I would agree about diet. Plus there are other things that people do for different things. Many islanders tend to have a diet rich in omega 3 because fish is primary in their diet, but even then, not all fish are equally healthy. Salmon vs. catfish. Catfish has more unhealthy fatty acid than Salmon. So I would think generations of eating certain foods will change our general appearance.

There doesn’t have to be much purpose when technology lets you live anywhere you want. I’m not an anthropologist but all you really need is the genetic luck of being popular to have your genes succeed in a given area.

You could have the least functional hair for cold weather but as a result of good technology, survive and procreate for generations.. you could fill a region with a people who aren’t best suited to their environment, selected only for their availability and not for their perfectly adapted hair follicles.

@ninjacolin of course that is true now. With the technology now there is no reason for a global species to produce regional varieties. Food from anywhere in the world, heat and ac, and the ability to easily relocate anywhere makes any original evolutionary adaptations moot.

@Pandora and @SavoirFaire I must admit, I never thought of died. Silly me.

And indeed, those distinctions are now very slowly disappearing due to relocation and intermarriage. I think that eventually they will be largely gone. [If the world lasts long enough]

I think the Inuits are some sort of fluke. I personally think it isn’t as much the D, but camouflage. If you have ever been to an icy environment like glacier bay in Alaska you know how blue and white the area is. Even the ice is bluish. So people in cold climates I believe blended in better with pale skin, blond hair, and blue eyes. In climates with four seasons white people are tanned in the sun like the bark on a tree to blend in and paler when the forests have grey tree trunks, snow, and grey skies. In the dense jungles of Africa people have blacker skin and black eyes. The deserts of the middle east their skin is more sandy colored. The Native Americans on the Americas often had reddish skin like the clay in their surroundings. I have never read anything that goes along with this idea, and when I asked a Q here about it pretty much everyone disagreed with me, but it makes the most sense to me.

I am pale pale white, but when I am in the cold weather I am all covered with clothing anyway. Even many 100’s of years ago they covered their skin in the cold weather. My skin is horribly inefficient, because I burn very very fast, so I don’t expose myself to the sun.

@SavoirFaire I think that ignores all the very white, blond blue eyed, people living in the Nordic countries who also eat fish high in vitamin D.

@JLeslie skin was never a protection from the cold. Skins of critters, maybe. But the Romans were always referring to the “hairy” barbarians of the north. Being covered in body hair might be useful. But then why didn’t monkeys and apes evolve as hairless? They all seem to come from hotter climates.

And was all the land surrounding native Americans red? Lots of green. Lots of good topsoil. Lots of grassy plain. Lots of tropical jungle.

You are leaving out climate. Europe is a rainy cloudy place so Europeans get even less sunlight than people in more northern latitudes. It’s all about the vitamin D as far as skin color and that is more or less mainly sun exposure.

@ARE_you_kidding_me climate was my main thought in the firt place, but temperature, not clouds. How do northern Europe’s clouds compare to southern Europe’s or to small island land masses like Micronesia or Hawaii? How do they compare to large land masses—both the coastal and inland? Clouds seem too much of a varable, and I think people can sunburn even on cloudy days.

Oh, temperature matters too, you are more likely to be fully clothed if it is cold out. It’s likely more complicated though when you start talking about temperature,clothing and diet. In general It’s pretty obvious that it’s mainly based on sun exposure. Thin clouds you can get burned but thick rainy clouds not so much.

@northwestern US is notoriously cloudy and rainy but the native American peoples from that region did not and do not look very northern European.

That’s true, It takes genetics though it could be that native american skin tone was “good enough” to enable survival. They may have also been more nomadic than europeans. I really think it’s kinda complicated but still more or less sun exposure related.

You are assuming that racial characteristics are a result of climate. People speculate on that issue based on sun exposure.

And perhaps that is not a bad notion. But I don’t think the hypothesis has any other basis than the observation that white folks from New York turn brown when they hang out in Miami.

I cannot prove it, but I would be willing to bet that the premise is wrong.

While it might be true that a pre human ancestor appeared in one spot and spread out…I bet humans became humans in different times and different places.

And I bet their different characteristics transcend skin color and eye shape.

I also bet politics, what ever side you are on, prevents a really objective study about the true facts about the evolution of humanity.

The idea isn’t that the light skinned folks will change, it’s that they will not survive as well and eventually the lighter characteristic will get diluted out of the population through attrition.
Politically I chase actual facts. right, left or sideways I don’t care.

@josie I actually think you are right, but as far as I know all present anthropological scholarship points to all mankind originating out of Africa with “Lucy” —and overpowering their Cro-Magnon/Neanderthal counterparts in Europe and whomever might have been elsewhere.

Different climates???

Obviously someone does not understand evolutionary theory.

@ARE_you_kidding_me of course. That’s called evolution and is what we are talking about—not sun-bronzing.

@anartist
Just to clarify my statement…
Cro-Magnon is Homo sapiens.
Neanderthal is Homo neanderthalensis
Or to be generous, Homo sapiens neanderthalensis

@josie oops, my bad with the Cro-Magnons. It was actually the Neanderthals I was referring to. apologies.

@Neodarwinian Perhaps you should explain this then.

From what I can remember of my reading the Neanderthals [from Neander Valley Germany and possibly spread somewhat through the middle east] lost the battle to Lucy’s people and became extinct. And I think they were supposed to be hairy.

Hey, maybe they didn’t, at least not completely. Maybe African Homo Sapiens [whatever they are called, “Lucy’s people”] raped some, took some captive for wives or slaves and the human race was modified that way in that region. I wish we knew more . . .

@anartist

Not to be argumentative, but…“Lucy” is not Homo sapiens.

“Lucy” is Australopithecus afarensis, a hominid, but not Homo.

@JLeslie Like I said, I don’t know how broadly the explanation offered by that article might apply. I will try to provide one possible answer that could be given on behalf of the researchers it cites, though. Here’s what I think they could say:

We have to keep in mind the role of genes. In general, a generation of light-skinned people will give birth to another generation of light-skinned people, and a generation of dark-skinned people will give birth to another generation of dark-skinned people. When there are no overwhelming evolutionary pressures, groups will change less rapidly.* They’ll still change, of course, since mutation is not something we know how to stop.

What this means for your worry, then, is this. The Nordic people you mention are the descendants of light-skinned people from southern and central Europe, whereas the Inuit are the descendants of dark-skinned people who crossed the land bridge between Asia and North America. Since the Nordic people were already light-skinned, and since there were insufficient evolutionary pressures for them to become darker skinned, they stayed light. Since the Inuit were already dark-skinned, and since there were insufficient evolutionary pressures for them to become lighter skinned, they stayed dark.

Diet, then, is the explanation for why the Inuit faced no significant evolutionary pressure to become lighter skinned. They were getting enough vitamin D without light skin, unlike the southern and central European ancestors of the Nordic peoples, and so no major changes came about. Or at least, that’s one way the researches cited in the article could defend their position. Whether or not there is enough countervailing evidence to undermine that argument is something I do not know.

——————————
* “Rapid,” of course, is a relative term. Evolution is typically an extremely slow process, so even rapid evolution will still be slow in all but the most extreme cases.

@ARE_you_kidding_me

Evolution is the change in allele frequency over time in a population of organisms.

This happens with the individual genome being selected against the immediate environment for survivability and reproductive success. Alsop sexual selection is at work in humans to a strong degree.

The question is an oversimplification ( climate ) of a pop understanding of evolutionary processes. In other words the question is very ill posed.

” Short kinky hair would be better at cooling the head in warm climates, while long straight hair better at keeping the head warm [I think]. ”

An example of what I am talking about. Makes no sense.

@josie, I stand corrected again. I did too much of this from memory.

You’re right. I thought one had been discovered after Lucy, but they are both of African origin. The naming of Lucy as Lucy belonged to the species Australopithecus afarensis (meaning Southern Ape of Afar) is confusing though since she was found in Ethiopia.

More on last find

More on Lucy

All Africa-centric research began with Louis Leakey

from above link: Louis Leakey had two main theories that he came up with throughout his quest to discover the origins of man:
1. That man arose in Africa
2. The australopithecines were an unsuccessful sideline which left behind no descendents

The way that he proved this was just through the evidence he found during his expeditions: the first australopithecine and many other artifacts, “Zinj”, a trail of footprints representing the 3.2 million year old Lucy skeleton, and lastly Homo habilis. Through all of this evidence it became obvious that man arose in Africa, not in Asia. So Leakey changed not only his life, but history itself.

@anartist Not all Native Americans have reddish skin. I just can’t help when looking at the colors of the environment that the people who live amongst those backgrounds kind of blend in. I was not saying skin is a protection from the cold. I am saying our skin is not exposed in the cold so it doesn’t matter what color it is in very cold climates. Also, very pale skin that burns is exposed less in the sun, because it burns. My husband is much darker than me, yet his D levels are fine without supplements (well he has I think 400 IU’s in his multivitamin) while I am extremely deficient unless I take mega doses of D. I take about 10,000 IU’s a day to stay up in the same range as him). Supposedly he has more protection from the sun than me, and would absorb less, because his skin is dark, but in fact he goes out in the sun and does not worry about protecting his skin so he actually gets a chance to absorb some D.

If you have been in the woods the green is typically a few feet to several feet higher than the ground. The trunks of the trees are what is predominent a few feet from the ground. If you live near deer you see their coats go from brown in the summer when the trunks of trees are brown, to havng grey fur to match the change in the trees and background colors. Most animals that are 3 to 6 feet are not green, but animals that lie low in the grasses are, and some of those that are up in the trees are also.

@SavoirFaire Supposedly all humans originated in Africa. The Nordic people might be decendents of southern Europe, but those people were decendents of African people. They got lighter and lighter as they went to more northern climates. There could be multiple reasons for the skin color changes. It could be a combination of D and camoflauge. Since the Inuits and Native Americans in general came over from Asia, I agree they start with a darker skin anyway. I don’t know if they came over to the Americas more recently than the Europeans moved from southern to northern Europe. I don’t know the timing well enough, but I assume there is information on that.

Also, low vitamin D doesn’t kill you in a day. People can live well past fertility age with lowish D levels. It’s estimated 25% of Americans have low D. When choosing a mate I am not so sure they would know to choose a lighter skinned person based on their D levels. Although, obviously if it was so low they had scurvy as an infant that would affect who is surviving.

What I am curious about is if the idea upsets you that the camouflage idea might play a part, or if you just simply think there is no scientific evidence?

@JLeslie Again, this is not my own argument. I linked an article that offered one possible explanation, and I have explained how the researchers cited in that article might respond to your criticisms of their position. As for your new criticisms, I’ve already explained the response that could be made to them. Nevertheless, I will do so again—this time in greater detail.

The researchers cited in the article would argue that people of southern and central Europe got lighter at least in part because they themselves were not eating a diet rich in vitamin D. Thus they became light-skinned, and the absence of pressures to become dark-skinned meant that those of their descendants who traveled further north and became the Nordic people would not have been subjected to sufficient evolutionary pressures to prevent the proliferation of these light-skinned genes even if the lack of vitamin D ceased to be an issue.

As for the bit about choosing a mate, they would probably respond by pointing out that evolution does not work that way. That is, people do not choose mates for explicit evolutionary reasons. Attractions can be reinforced by evolution if those with certain attractions are more likely to survive long enough to reproduce and raise their children, and they can be reduced by evolution if those with certain attractions are less likely to survive long enough to reproduce and raise their children. But in no way would changes in skin color need to rely on conscious mate choice.

This isn’t to say that such things had no part in it. Many cultures have valued lighter skin for various reasons, and so that would add a social factor into the natural evolutionary process. The point, however, is that the researchers cited in the article need not appeal to such possibilities to defend their point. It would be enough to show that not suffering from a vitamin D deficiency made one less likely to die before reproducing and/or more likely to have a larger number of surviving children.

These effects could be achieved in either of two ways: (1) the children could be better off due to the direct benefits afforded them by their skin tone in the northern environment, or (2) the children could be better off due to their parents being healthier for a longer period of time (and thus garnering a greater share of the available resources, including those that might be devoted to child care). The latter point would be one way of responding to what you said about living past fertility age with low levels of vitamin D. It’s not just reproducing that matters, but the relative ability of one’s children to reproduce as well.

Regarding the timing of the various human migrations, Europe was settled 40,000–50,000 years ago, whereas the earliest migrations to the Americas happened 7,000–15,000 years ago. We have to remember, however, that there were several migrations out of Africa. It’s not a single line of people splitting up in various ways, but rather several separate groups setting off in different directions at different times.

Finally, nothing in my previous post had anything to do with your camouflage hypothesis. It was a response only to the single sentence you addressed to me in your first post, and one made on behalf of the researchers you were criticizing. I am not “upset” by your hypothesis, nor did I address it in any way. It was not, after all, part of what you directed at me. Since you asked, however, I am not aware of any scientific evidence in support of the camouflage hypothesis.

Moreover, it seems somewhat dubious in light of the fact that many people cover most of their bodies with clothing (thus limiting the advantage that skin tone could play in camouflaging them) and that few skin tones are adapted to their environment in this way (despite the fact that the putative evolutionary pressures don’t seem limited to any particular subgroup). Then there’s the problem of red hair and the fact that blue eyes are in no way limited to Nordic peoples.

I just read an article that says that the inuit people have only been north for about 5 thousand years and so it may not have been long enough for evolutionary changes, and that there diet is high in vitamin D so they may not be a reason for the physical change to happen.
Here is the link.

@Neodarwinian So what exactly is your problem with climate being a driving force for selection then?

@ARE_you_kidding_me

Is gasoline the only driving force in your car’s engine?

I said environment and I meant environment. Climate is a small piece of the driving force in human evolution and the matter under discussion is too complex for armatures and their speculations.

Why are you even arguing this? I agree with you