humans originally black?

I had a geography teacher who claimed that we’re all black, because geneticists have proven that it’s impossible to get black skin from uh, white skin DNA (for lack of a better term). So we all started out dar, and over time, recessive freaks showed up with white skin.

To me, this goes against the evolution theory. I was always taught that peoples of different regions developed skin color that would suit the region. Black skin is better for hot, sunny places. But this doesn’t make sense either, because black skin would be fine in the polar regions. So why would white skin appear? Extreme lack of sun to color the skin? Even over millions of years, it seems unlikely that non-albino skin could reach such a pallid degree, especially considering that if it’s true that the human species originated in the Mid-East, it would take millions of years just for people to travel that far away.

Also, most animals I can think of that are closely related to us have light skin, usually pinkish or greyish. Many have dark fur, but light skin under it. Are these geneticists saying that we’re so similar to other primates’ characteristics, but opposites in pigmentation? It doesn’t hold up. Or does it?

I’m sorry for the long post. I’d appreciate responses to any or all of the ideas of this little homily.


I don’t know who first said “everyone’s a critic,” but I think it’s a really stupid saying.

You really have to be careful who you listen to on this issue, because certain viewpoints come from people with an agenda of racism ( or religion). The 5% believe that the black race was created first. Of course many white supremicists claim that either whites were created first, or that the white skin is most removed from our neanderthal origins. I always wondered why the evolution theory would support that white skin was the epitome of our evolution, since it is obviously not the best pigmentation for survival, in that it is pre-disposed to burn more easily. However, I would think that (just as now) people of the same pigmentation would tend to mate together. If the first darker complected people tended to mate with darker complected people, and so on, eventually you would have distinct races. Just my thoughts.

This is how it was explained to me:

The race that’s been around longest is the race which has the most variation.

Thus, the Caucasian race (the skin-colors of which range from very pale to jet-black, with similar variation in hair and eye color) would be the oldest.

It should be noted, however, that this was explained to me by an old-school-white-southern-boy Genetics Professor, so I guess some racial bias could have played a part.

>The race that’s been around longest is the
>race which has the most variation.
Does this theory fit ANY other species of animal besides humans, or animals egineered by humans?

Is it not generally accepted that humans originated in what is now Africa? Thus, the variations occurred after we spread from there, right? We’re talking science here and not myth or politics, right? Anthropology as opposed to the official platform of the Southern Baptists?

If we are to follow available evidence humans have been on this earth a very short time.
As for race, this has been covered before.
DNA testing done about 6 years ago concluded that we’re all related to each other.
The surprising DNA revelation was who was “farthest” from each other. The two races who were least related to each other were Africans and Aborigines.
If we learn anything from DNA testing it is that skin color is not very important. Whether or not we choose to accept this is another matter.

TennHippie, I have read that we originated in what is now Africa/middle-east, which I said in my original post. That very point goes against the theory that we adapted to our environment, given the limited time to lighten in color.

To Doug Bowe and all else, this is purely scientific. I am most certainly not postulating that a certain color makes a better person. Though I must admit I have one prejudice; I’m biased against people who express prejudice.


I don’t know who first said “everyone’s a critic,” but I think it’s a really stupid saying.

To the best of my understanding, the human race originated on the savannahs of east africa. Once we moved out of the trees and into the open dark skin became dominant because high levels of melanin protect us from sunburn (which is why caucasians tan).

As we moved further from the equator into regions where we were exposed to less sunlight, dark skin created a problem. We require sunlight to metabolize vitamin D. A darker-skinned person requires more sunlight, on average, to produce the same amount of vitamin D. In the absence of fortified whole milk and Corn Flakes, evolutionary pressure favored lighter-skinned people in Scandinavia.

I emphasize that this is only a theory, but it’s the best explanation I’ve heard for the appearance of lighter skin colors in northern europe.

Pete, re-read your own OP. You never mentioned Africa in it, and I also got confused. You just said “Mid-East”.

There is only ONE human species, races are better defined as “sub-species”, and “caucasians” (another racist term invented by some very prejudiced “scientists”) are not “opposite” in pigmentation to africans, native americans, or asians. It’s the concentration, so to speak, of melanin that makes skin tones darker or lighter.

In an article from Discover Magazine, “How Africa Became Black” (february 1994), Jared Diamond says: "…the africa encountered by the first European explorers in the fifteenth century was already home to five human races: blacks, whites, Pygmies, Khoisan, and Asians. The only race not found in Africa is the aboriginal Australians and their relatives.

May I suggest you go to this page?

http://http://www.discover.com/archive/index.html

for TOPIC choose “anthropology” and for keywords in title, “human races”.

It might help you.


Men will cease to commit atrocities only when they cease to believe absurdities.
-Voltaire

One of my college biology instructors told my class that the Australian Aborigines had been isolated from the rest of Homo sapiens for so long that they almost qualified as a different species. This was supposed to be based on one of the means of determining different species - that matings between animals that were less than 75% fertile meant they were different species, and Aborigines were right at the 75% mark when mating with the other human races. Has anybody else ever heard this?

sosumi

Skin color is a product of natural selection. Natural selection is a product of environment. The climate (or environment) of Africa 50,000 years ago was very different than it is now (or even 20,000 years ago.) Trying to guess the skin color of the original humans is about as futile as guessing the shape of a homo habelis jaw without actually having the fossil remains of a skeleton.

Coosa:

You shock me! Please give me your “instructors” address so I can send him a nice “gift”!


Men will cease to commit atrocities only when they cease to believe absurdities.
-Voltaire

I wonder about that vitamin D manufacturing “problem” for dark-skinned humans. As far as I know, any of us can make all the vitamin D we need with as little as 15 minutes exposure to full sun every day.
Could that time span be increased so much that it would really make a difference simply by the presence of more melanin?

Thanks to E1skeptic for finally questioning the use of the term “race,” which the rest of you seem to take for granted. It’s an outdated non-concept, never adequately defined, and only really useful for pseudo-scientific attempts to justify racist beliefs.

No race has been around longer than any other because there is only one race, the human race. Due to evolutionary biology, certain groups of people have some superficial visual characteristics that make them look a little different on the surface. That does not separate us from each other, and you can’t possible pinpoint a different time of origin for each of these so-called “races.” If a certain region or community had only brunettes, would you start clasifying them as a “dark-haired” race? Or would you realize that the absence of a gene for blonde hair is too insignificant to make such a distinction? It’s pretty much the same thing with skin color.

>CFQWEST
Its not the same for skin color at all. There is not a black/white gene. Dark skinned people dont have light skin kids and vice versa. Light and dark have kids, kids are in the middle.
As far as I know skin pigmentation is widely accepted as a survival addaptation. I haven’t heard the same about hair color. The original question was, if the original humans had dark pigmentation, why would they loose it? If they were originally pale, how did they come to be so dark only in the africas and austraila? Dark skin seems like a superior genetic trait in any climate.

Here’s what Cecil had to say (somewhat obliquely) on the subject -

http://www.straightdope.com/classics/a1_099.html

I don’t know the answer to that Nickrz. Here’s a thought though. Along with the sun being lower in the sky at high latitudes, people have to cover up a greater percentage of their skin for a greater percentage of time (especially in winter, when the sun is lowest in the sky and only up for 6-8 hours). Could a serious vitamin D deficiency manifest itself over the winter?

In the column you refer to (above), Cecil notes that skin pigmentation in caucasians can generally be correlated with latitude. It seems reasonable that, in the past, darker skin was selected for in groups living at low latitudes (not consciously, but because lighter-skinned individuals tended to get skin cancer and die).

Pete originally asked why black skin would be a problem in polar regions. My reference to vitamin D was an attempt to come up with one possible (albeit untestable) explanation. I am certainly interested to hear other hypotheses.

Mammals protect themselves from the sun in two ways: melanin and hair. Caucasians have the least melanin and the most hair. Among whites, blondes have more hair than darker-haired people (i.e. more follicles per skin area). Blacks have less body hair generally than whites. How the correlation works with Native Americans and Asians I don’t really know.

I can imagine our very hairy ancestors in ancient Africa having light skin beneath - like most mammals. IF one hypothesizes some pressure to lose body hair, those in environments with strong UV would naturally develop greater melanin production (we would expect convergent evolution wrt skin color in Africans and Australians, whenever their most recent common ancestor lived). In colder climes, the tendency to hair loss would be reduced since it would be needed for warmth as well as a UV screen, and the need for melanin would be less in higher latitudes if hair loss DID occur. I can understand the melanin split if someone can explain why we would need to lose body hair.

One explanation I’ve heard is that it is a swimming adaptation, though I’m not sure I buy that. Anyone have any better ideas?

The vitamin D thing makes some sense, especially with the advent of clothing.

Evolution works in mysterious ways…

Have you given a thought at recessive genes+mutation+artificial selection+natural selection?

Too many variables, huh?

[[Thanks to E1skeptic for finally questioning the use of the term “race,” which the rest of you seem to take for granted. It’s an outdated non-concept, never adequately defined, and only really useful for pseudo-scientific attempts to justify racist beliefs.]]

It’s easy to say it’s an “outdated non-concept” if you’re white in America. If you’re black, in particular, it’s a very timely, relevant issue.