Ok aswokei, seeing this has become an arguement about race I am compelled to add my own opinions here. PLEASE read this all the way through, I hope you'll find it quite revealing.
There are some major flaws with your arguments.
1) Your definition of intelligence. Have you really thought bout what 'intelligence' is? I don't there's a scientist out there who can answer this one simply. You want to use 'IQ' as your measurement. Ok, as someone mentioned earlier, IQ is an ethnocentric measure of intelligence, based on western concepts and constructions of intelligence. This basically means, they are culturally biased tests, made for white people, by white people, if you like.
2) Your second problem is your steryotyping of 'race' into these three arbitrary categories (white, black, hispanic) which I quite frankly find laughable, but it continues to shock me how many people have this bizarre conception of 'race' based on skin colour.
Skin colour is determined by one gene which regulates the production of melanocytes, the skin cells that produce melain, the brown skin pigment. Even if, for some bizarre reason, you decide to categorise someone by their skin-melanin levels, what you will find is a CONTINUOUS scale of colour from very light skinned people to very dark skinned people. Did you know there is a greater diversity of skin tones within Africa than between Africa and the rest of the world? Where, exactly, do you draw the line between someone being black and white?
Now, lets think about this. One gene determines skin colour. Now, what makes you think this skin colour gene is linked to, lets say, an 'intelligence gene'. Are all people with blue eyes also extremely tall? No. Why? because there is no link between the genes. When two people mate, their genes go through a process of recombination, meaning any gene from one person's chromosome can be mixed with any gene from another person's matching chromosome. There is probably no link between genes for brain development and genes for skin colour.
Ok, enough about external differences between human populations. What about internal differences? Skin colour is an arbitrary classification. So lets take something else arbitrary...the ability to digest lactose in milk. People from south east asia tend to lack the gene that encodes the enzyme lactose dehydrogenase, which can break down lactose in milk. Why not categorize people by the difference in this gene, rather than the melanin gene? Instead of 'black' and 'white' people, we could call them 'milk digesters' and 'non-milk digesters'. But isn't that just as a rediculous classification as skin colour?
Also, you will find you are likely to have more genes in common with someone of a different colour who lives in Africa than to your white (or same coloured) neighbour next door to you. As I said, skin colour is determined by one gene only. Every person is as genetically different as anyone else. The thought that you have more genes in common with someone of the same colour as you is as stupid as saying your are more likely to have more genes in common with someone who has the same eye colour as you. The one major difference in genotype and phenotype within human populations is actually between men and women. Like the eye colour thing, are you trying to tell me you have more DNA in common with a woman of the same colour than with a man of a different colour? Sorry, you're wrong.
Ok, so, your classifications of race are totally invalid, and 'race' (especially race based on colour) as a biological concept has been completely debunked if you know anything about genetics. Also you have no idea what intellence is or means.
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Right, so lets get on to why there may be differences in 'intelligence' (or, I should say, the ability to perform well in an ethnocentric american intelleigence test) between people who have different amounts of melanin in their skin.
Well, it is, entirely I will bodly claim, environmental. You seem to completely ignore the history of humanity in this arguement. Since European imperialism beginning shortly after the 'enlightenment' in the 16th and 17th centuries or so, people of darker skin tones have been opressed by people of whiter skin tones. If you want to go back further, the same thing happened in the Middle East during the crusades. But, why, I hear you ask, did white people manage to be 'superior' to dark toned people. Dumb luck. The humans who migrated north from Africa a couple of hundred thousand years ago (who were black, I hassen to add) gradually developed lighter skin tones in a reaction to the lack of vitamin D which was normally gained through exposure to bright sunlight (which you get too much of in Africa). Lighter skin tones meant more sunlight reached the skin which meant more vitamin D could be produced, which is essential for bone integrety. So, we now have a population of light skinned humans living in Europe. Now look at Europe's climate. Nice and mild, pleanty of water in the winter, enough sun in the summer for crops, and pleanty of fertile land and resources. So we developed civilisation. We developed technology. We developed IQ tests to show how bright we were. Then we started exploring. (All this, by the way, happened in the far east as well, with a similar climate and land zone type). So this explains why dark skinned people in Africa didn't become industrialised like Europe (and later..America) did.
So, now I hear you ask.....without reading, without civilisation and without technology, how could black people in Africa ever become as intelligent. Ok, well here you're making another mistake.
Being able to read, and having the capacity to learn how to read, are both very strong indicators of intelligence. Every normally developed human in Africa has the capacity to learn ANYTHING and EVERYTHING a white European or American child can. They just don't, as has been pointed out, have the resources to display this in ways us 'civilised folk' understand.
So why the poorer IQ scored in black Americans, and why the higher crime, birth rates etc? Errr....hello? 300 years of white oppression anybody? 300 years of being denied a quality education, 300 years of not being picked for a job because of dark skin, 300 years of police prejudice, 300 years of not being able to get a bank loan to put the deposit on the house in the nice part of town....I could go on. Black people may be less educated (and thus find IQ tests much harder) but that is VERY different from being less intelligent.
Any claims of whites being more inteligent than anyone else as a population is so ridiculous and fundementally flawed on so many levels I CAN'T BELIEVE in this day and age people still think this way. It just doesn't make sense.
Ok, that's the end of my rant. Oh, I have white skin by the way, although I have a black skinned great grandfather, which, in itself, shows how misinformed your arguement is anyway.
