Yet not one of you can actually provide scientific proof of your claim that we were white men that turn black later, got it and done with this nonsense trying to be pushed here as actual science.
Ok, well first of all, I've made no such specific claims, so ya ought to calm yourself down and pay attention. As I said earlier there are contradicting theories. Go back and read the links I provided. Both of which bear far more weight than your unscientific skepticism. Your foot stomping insistence is the epitome of anti-science. Evolution is indeed NOT a one way street. It has no specific path and can easily reverse itself.
Calm down? LOL! I am as calm as calm can be, you must take this much more serious than I. Except that all the real science backs up what I stated and I even tried to make easy by posting links to just a handful sources out the countless studies that have been performed, and yet you and others ignore the facts still. I never said it was a one way street, yes there is evidence that some animals did change back into water living creatures, but there is no evidence that we ever changed from a white creature to a dark one. Deduction from the known facts is scientific methodology, as in Evolution being accepted as Fact based on the mountains of evidence from every earth science practiced, I have yet to see any scientific evidence of the claim made in this thread, but yet you guys question the evidence that is available. So be it, believe what you want, it does not matter to me what nonsense you want to believe in, heck if you say you believe in the tooth fairy that is your business, just do not say it around adults and I would suggest not going into any University Anthropology Dept. and spouting your theory that black men evolved from white men, the laughing at you would be endless.
it is not unreasonable to believe that when homo sapiens first lost their thick coats of hair, they had lighter skinned underneath that evolved into being black in warmer climates and stayed lighter in cooler ones. were they blond hair/blue eyed???? most likely not. were they brown haired/brown eyed? I'd say most likely.
What does it really matter? To me the only really interesting thing about the thread is why the palms/soles don't have the pigment. That has pretty much been answered, and it really has nothign to do with the sun.
Modern humans acquired a light skin pigmentation allele through the A111T mutation commonly shared among the populations in the Middle East and Europe. But prior to the lighter skin mutation that differentiated West Eurasians from East Eurasians, it was after Neanderthal admixture when Eurasians became pale skinned compared to sub-Saharan Africans and Neanderthals provided modern humans with adaptive variation for skin phenotypes such as BNC2 and POU2F3. It's estimated that 35-70% of the Neanderthal genome still persists in the DNA of present-day humans, with East Asian individuals inheriting 21% more Neanderthal sequence than Europeans.
Think about how genetic change occurs, if a mutation such as skin colour occurs is it going to affect each indiviudal skin cell or all of them at once?...if there is no disadvantage to butt crack or armpit cells being a different colour they'll go along for the ride...
what BS...you haven't supplied any evidence other than your straw man to show we originated in africa which absolutely no one on this thread has denied... whereas I did post article referring to an anthropological study by Nina Jablonski, now chairman of the anthropology department at the California Academy of Sciences found that 5 million yrs ago our ancestors were originally light, apparently no one is laughing at her...
There are millions of people with skin as dark or darker than west equatorial African blacks ("Congo" variety). Nevertheless, these millions of dark skinned people are still considered white people and are fully accepted as such. There are millions of "Congo"- type people in Africa and throughout the world, including African Americans who have skins as light or lighter than the white man, but these people are still regarded as being ordinary blacks and are discrimminated against. Contrary to what liberals say, it's not skin color that matters -- it's mannerisms, facial features, culture and behaviour that distinguishes black people from white people. But who has the right to judge that one culture and behaviour is better than another? I am originally from Spain and have dark, swarthy skin. But I'm still regarded by everyone (except maybe an isolated redneck in Alabama), including the census, as a white man and cracker. (I'm so "white" that I cannot even claim ethnic minority status.) Darn it! Gracias
Thanks for the link I remembered the basics that the skin on your palms and soles is different than the rest of the skin on your body but didn't remember all the details. But its nice to know that after so many years I still have the basic facts right. Its skin geared towards creating callouses and has very little pigment.
that seems to be his approach...make a claim no one disputes, supply no evidence refuting the op and ignore any evidence that supports the op's position...
AN EVOLUTIONARY MODEL FOR SKIN PIGMENTATION "We have combined our results with those from other studies to form a simple and somewhat speculative model for some aspects of the evolution of pigmentation in humans. Our model is displayed graphically in Figure 1, which shows an average tree of the three HapMap populations, with general skin pigmentation trends indicated by shading on the branches. This human tree would join with a hominin ancestor who likely had light skin because of the protective shielding provided by complete body hair coverage (6). It seems plausible that coincident with the loss of fur in the lineage leading to early Homo sapiens, there was strong selection for skin darkening (Branch 1 in Fig. 1; 43,44). Selection-nominated pigmentation genes on this branch include MITF and EDN3, which show evidence of common negative Tajimas D across all three populations. Later, the African and the proto- European/East Asian populations diverged upon the out of Africa expansion (Branch 2), followed by the splitting of East Asians and Europeans (Branches 3 and 4, respectively). Previous evidence (17,22) indicates that the genetic mechanisms resulting in the light skin of both Europeans and East Asians may be largely different and therefore did not evolve prior to their population divergence. However, some candidate genes show evidence of selection in both populations, which may be indicative of an important role predating any divergence (Branch 2) or the independent evolution of the same function in both populations (Branches 3 and 4). To help distinguish between these possibilities, we supplemented our initial analysis by examining the presence of haplotype sharing (in 200 kb regions centered on several nominated genes), which helps us to distinguish whether the haplotypes present in populations showing signatures of selection are the same in the two populations (suggesting Branch 2 localizations) or different (suggesting Branch 3 and 4 localizations)." You should: Learn how to insert an actual Link in your posts. Read more closely what you claim supports your theories. The First MEN were not white, once the ape started lossing hair it became dark and ther ya go. Enough of this.
His arguments a very clearly an Afrocentric. No amount of scientific evidence will dissuade him from making pseudo-scientific arguments.
yeah, I'm fine with the all the evidence of us all being dark when we left africa but it's illogical/irrational for him to claim(with no supporting) evidence that we weren't previously light when we evolved from fur covered to naked...
Its Afrocentrism it isn't supposed to be logical. Afrocentric Americans insult every other culture and people who call Africa home.
Also "white" persons show the same phenomenon [when we get tanned]. So, it's a false discussion: it's biology. Since the palms of the hands [like the palms of the feet] are surfaces of contact and of application of force the body concentrates keratin there and it reduces the pigment. With this, add that there is a further lucid layer which is absent in areas of not application of force. So, what are we talking about? Do you want a prove? Think to when you've got a callus: it's well more clear than the surrounding skin.
I've seen three explanations, one claims its a protein that blocks the pigmentation a 2nd claims there are fewer cells that produce pigmentation in our palms and soles and a 3rd that claims there are the same number of cells but because our skin is thicker on our palms and soles the pigmentation doesn't get through...which is correct? They all seem plausible...but whatever the reason its the same for dark and light skinned people...
In fact, now that it's summer, I'm tanned and since I'm Italian I tend to become quite dark, but the palms of my hands remain quite light [and I'm just observing them now]. Why? Sure it's a matter of pigment [it allows skin to be tanned]. The external thickness of the skin affects pigmentation, no doubt: the thickness of the skin can vary from 0.5 to 2mm, commonly, but it reached the value of 4.0mm on the palms [of hands and feet] and on the rare part of the neck. Also the thickness of the skin reduces the efficiency of the pigmentation. And the thickness of the skin [like the concentration of keratin] is connected with the usage of an area of the surface of the body [where we apply force we need more resistant skin ... so more thick.
You say all the ‘real science’ supports you. What are your qualifications to judge what is real science and what is not, particularly in the field of evolutionary genetics? You have not produced any evidence. What you have produced is an unsubstantiated connecting of the dots and a great leap of unscientific faith which may or may not be valid then attempted to validate that theory with a video that has been pulled for copyright violations and an article that says nothing about skin pigmentation. Here’s what you said. Clearly you show skepticism that the evolutionary process can only go in the direction you desire. I graciously corrected you on that silly notion. That you feel violated at my offer to educate you is your problem. The scientific method does not allow you to selectively pick your data and deduce from only those observations that support a pre-conceived conclusion. You don’t get to summarily pick and choose what is good science and bad. Furthermore since you have provided little to nothing in the way of evidence, I have to question your claim that we question the evidence. And, if you possessed even a basic understanding of the scientific method you would know that the first thing a ‘good’ researcher does is to question and challenge his own conclusion. Your scientific method [LOL] here appears to be ‘I’m right, you’re wrong SHUT UP!” That’s not scientific at all. Hissy fit…Again, calm down. And once again I must remind you that it is not my theory. I merely presented a counter theory to your foot stomping insistence that it must be your way and no other.
Do you have issues with the study? Wanna talk about it? http://hmg.oxfordjournals.org/content/15/suppl_2/R176.full
I think blacks have higher levels of melanin which is the substance that causes skin cells to turn dark when exposed to ultraviolet rays. The theory is that human beings from near the equator naturally developed more melanin to block those ultraviolet rays which can be damaging. Humans from the northern climates, where the Sun's rays are weaker (as they hit the Earth at an angle) have less melanin in order to gather enough sunlight to create such things as vitamin D. These folks need artificial sun block for protection from the Sun when exposed for periods of time in more direct sunlight. I believe that some blacks will have lighter skin in unexposed areas.
in regards to your link the oxfordjournals the diagram within it shows three branches with the african being darker than the euros and east asians, but then there is there the andaman islanders who are as dark as any west african but genetically they're east asian, genetic relatives of the Ainu of japan apparently...black skinned orientals...
I mostly agree with those two but also think there more factors involved, sexual selection and genetic drift..northern euros are very pale but there are others who live just far north who are not that pale....and others who live in the same latitudes as west africans who are not nearly as dark...and why are the asian andaman islanders black like africans while Indonesians who live further south on the equator are not?...
