If you don’t believe in Adam and Eve as portrayed in the Bible, please do not engage in arguments to the contrary. Just humor me and live with me for a moment in a world where the Bible is true and speculate on how the genetics would have worked.
Assuming the human race started with one man and woman and all races from them, I contend they would be black and probably wooly haired. I’m wondering if my thinking if flawed because I’m looking at it as black skin and black, curly hair as being dominant traits. As far as what’s actually been observed (very important) in science, mutations always take away useful genetic information, not add it, so it seems to me that white could come from black, straight hair from curly hair, but it seems far less likely to me that black could have sprang from lighter skin or curly hair from straight hair. I remember reading a couple of years ago where it was discovered that all blue eyed people descend from the same ancestor who had a genetic mutation (resulting in less pigment) and this sort of sent me on this line of thinking. Is my reasoning flawed?
Acemaster, thx for your contribution, but I do know for a fact that blond hair and blue eyes are recessive traits. Two blond hair, blue eyed people will always have blond haired, blue eyed, kids.
Norm, are you saying that vitamin D production would continue to increase from generation to generation and thus melanin production would increase more and more with each generation that is exposed to more sun? That sounds like skin color is not a matter of genetic characteristic but of the adaptive capability already programmed in the DNA; unless you’re suggesting that somehow the exposure to the sun stimulates changes in the DNA that would result in more melanin production; or perhaps that natural selection would produce the is result as the migrators would begin to feel more and more that black is beautiful.
I don’t read the bible but I know about Adam and Eve and your point is very reasonable. I think you could be right.
July 1st, 2009 at 9:25 am
The problem is that you’re trying to somehow combine scientific principles with something that lacks any scientific nature, religion. So I’m afraid there is no perfect answer to your question. (Well, you’ll certainly not choose mine:)
July 1st, 2009 at 8:31 pm
The primordial ‘Eve’ , not religiously, the common female to which all of our genetics can be traced, was most certainly black, in Africa.
July 2nd, 2009 at 8:21 pm
I don’t know, but I do know that the first PROVEN people on earth were black.
July 4th, 2009 at 9:38 pm
No they weren’t.
The garden of Eden is not located in Africa, therefore they
July 7th, 2009 at 12:34 pm
maybe, no,.
i think, they weren’t black nor white.,.,
maybe, they just have the average skin tone,.
well, i dunno, who knows?
July 8th, 2009 at 11:08 am
This is a possibility. Adam and Eve is generally portrayed as the culture they are being told to. For example, a Chinese book about them would feature them Oriental, and African, black, and an American, white.
Of course, they can’t be all of them. So, what were they?
I don’t know. No one really does, because they were so far back in history. Anyway, I believe, but I’m not sure, that they were white.
You said that you are considering black skin dominant? I don’t think it is, but it could be. I’m not heavy into genetics myself. I do believe that blond hair is in fact dominant, along with blue eyes. Could be black skin, but I can’t think of a time I saw a natural-born blond, blue eyed, black child.
Hope I helped a bit!
July 8th, 2009 at 1:23 pm
if adam and eve were black wouldn’t every human on earth be black. it’s possible that one was black but i’m not so sure.
July 9th, 2009 at 1:12 am
If you assume, as you do, a single pair of ‘original humans’ the biblical connection would imply that the pair would be brown possibly Arabic in appearance as the ‘garden of eden’ was surely situated in the Middle East, the location for most biblical stories.
Skin colour is most strongly related to latitude of habitat and the subsequent strength of sunlight encountered and is directly related to the production of vitamin D during exposure to light.
If we again for the sake of argument assume an African origin of the species then they would indeed be black skinned as the tropical sun promotes rapid production of vitamin D, then, as species migrated North, production was compromised by the northern sun and hence lighter skinned individuals had an advantage over their cousins.
As the estimated migration time has been only 40,000 years the transformation from ‘black’ to ‘white’ is a very quick mutation and there is little doubt that the return mutation would take a similar time scale.
Your biblical Adam and Eve would have given rise to offspring who moved both North and South resulting in today’s mix of races.
July 10th, 2009 at 8:14 pm
> “I’m wondering if my thinking if flawed because I’m looking at it as black skin and black, curly hair as being dominant traits.”
It doesn’t matter which is the dominant trait. What matters is which trait is selected for and which is selected against in the given environment. In tropical areas dark skin is selected for because too much UV radiation destroys folate in the body, which leads to birth defects. In higher latitudes lighter skin tends to be selected for because low UV radiation leads to low vitamin D production.
> “As far as what’s actually been observed (very important) in science, mutations always take away useful genetic information, not add it”
If by “information” you mean mutations can’t add useful heritable traits, you’re quite mistaken. Here are some examples of known beneficial mutations:
(antibiotic resistance) (increased virulence of 1918 flu) (A mutation in strep bacteria causes them to become “flesh eating” and increases production of a protein allowing them to evade white blood cells.) (mutation in ancestral gene linked to increased learning and memory in humans) (duplication & subsequent mutation of gene in apes allowing increased neurotransmitter flux). (recent mutations in people of East Africa allowing them to digest cows’ milk).
These are just a few of the cases for which we know the specific genetic changes responsible for the observed adaptations. More commonly, we’ll note that a new adaptation has popped up in a population, but we don’t know the specific genetic change involved. Such adaptations are still commonly due to mutations however. Even more common are the mutations that don’t produce obvious adaptations, but simply provide more variability in particular traits such as body size or skin color. If particular body sizes or skin colors subsequently do better in particular environments, then those become more common due to natural selection, and mutation subsequently produces new variability around the new norm.
> “it seems far less likely to me that black could have sprang from lighter skin or curly hair from straight hair”
That’s not how it works. It’s not a case of a skin gene including lots of information for pigment, and the skin becoming lighter as that information is lost over time due to mutations. There is no information for pigment (or hair curls) in a gene. Genes specify how to make proteins. That’s the information they carry – which amino acids to link in which order to make a particular protein. The identity and order of the amino acids determines the shape of the protein, and the shape of the protein in turn determines what the protein does in the presence of other molecules. So changes (mutations) in the gene can change the shape of the protein and thus lead to different mophological effects. It’s just as easy for a mutation to cause increased pigmentation or curlier hair as it is for one to cause decreased pigmentation or straighter hair. South Indians and Australian Aborigines tend to be quite dark skinned, but they are most closely related to lighter skinned populations in North India and Malaysia, repspectively.
> “That sounds like skin color is not a matter of genetic characteristic but of the adaptive capability already programmed in the DNA; unless you’re suggesting that somehow the exposure to the sun stimulates changes in the DNA that would result in more melanin production”
The “adaptive capability already programmed in the DNA”, in this case, would refer to an individual’s ability to tan. The general term for this type of variability within a single individual is “phenotypic plasticity”. An individual’s ability to tan (or lighten) does affect her exposure to UV radiation, and thus moderates any deleterious effects from too much or too little sun, but dark-skinned people aren’t merely better tanned. They inherit darker skin to begin with because, in the past, those individuals with lighter skin left fewer descendants. They left fewer descendants because the UV radiation in the tropics degraded the folate in their bodies causing them to produce fewer healthy babies.
Regarding your original question: since the first humans apparently lived in Ethiopia which is tropical, they would very likely have had dark skin. Hair type is less clear, but a genetic comparison of human populations (2d page here: ) indicates the European and East Asian populations descended from a particular population of early Africans. Most of the existing African populations have curly hair, so that implies the first humans did too.
July 12th, 2009 at 10:14 am