Human evolution and differentiation of races

[bpesta22]

No, I think the burden's on you: show me the study that when controlling for group differences in prenatal effects of alcohol, the group difference in IQ goes away.

FWIW, I do think prenatal issues and/or nutrition are likely causes, but I need to see the data. Please post it, if you know of it.

 

[Michael Redman]

Whom are you referring to here as making such pretenses?

I'm referring to the classification of people into races.

 

[Cavemonster]

Can you argue that the amount of genetic code which produces a blond vs a brunette is less than the amount of genetic code which differentiates a black from a Caucasian?

This comes up a lot, and while I'm on the fence as to how meaningful "race" is, the idea that there is more difference in code between within "races" than there is between them is not necessarily a compelling argument for the non-existence of "race" as a meaningful divide.

Here are four recipe's ingredient lists:
Sugar Cookies
Flour
White Sugar
Butter
Baking Soda
Salt

Poison Sugar Cookies
Flour
White Sugar
Butter
Baking Soda
Rat Poison

Oatmeal Rasin chocolate dipped cookies
Flour
White Sugar
Brown sugar
Instant oatmeal
Bittersweet chocolate
Rasins
Walnuts
Orange Zest
Butter
Baking Soda

Poison Oatmeal Rasin chocolate dipped cookies
Flour
White Sugar
Brown sugar
Instant oatmeal
Bittersweet chocolate
Rasins
Walnuts
Orange Zest
Butter
Baking Soda
Rat Poison

There is far more variation (in terms of number of ingredients that differ) within the poison/non poison categories of cookie than there is between them. In fact there is only one difference between them. Does that mean that the category of poisoned cookie is meaningless?

No.

You can't treat a genetic code as an undifferentiated hit or miss.

 

[lomiller]

Not by YOUR definition.
(Or mine, FWIW).
But that was my point. Different people use such labels differently, because that's all they are. labels.

Taxonomic rankings are defined by the International Commission on Zoological Nomenclature.

 

[sphenisc]

Race requires distinction, not difference.

Even if we stick to something as superficial as skin color, you cannot make the claim that there are apparent distinctions unless you can point to the apparent delineation between one group and the next. In other words, line up every human, darkest to lightest, and show where the apparent delineations are between one race and the next. If you can't, then the races are not distinct as to skin color. It isn't enough to pick two people out of the line and say they're apparantly different.

Now line everyone up, tallest to shortest. How do your races look now, with The Dutch and Kenyans tending to stand on the opposite end as the Japanese and Nigerians? Is the black race unusually tall, or unusually short? Are the Dutch and Kenyans the same race, due to their common characteristic?

Are blue-eyed, black-haired Afghans the same race as blue-eyed, blonde Norwegians, or as brown-eyed, black-haired Persians? Where is the distinct delineation here? If there isn't one, then the classification of these people into distinct races must be arbitrary.

If I do the same experiments with set of creatures called cats'n'dogs and can't find any distinction, does this prove there are only cogs?

 

[Kotatsu]

Now line everyone up, tallest to shortest. How do your races look now, with The Dutch and Kenyans tending to stand on the opposite end as the Japanese and Nigerians? Is the black race unusually tall, or unusually short? Are the Dutch and Kenyans the same race, due to their common characteristic?

Except that that is not how you would proceed. What you would do would be to take in all characters and data available, and on the basis of that try to find delineations between groups (if there are any). That both Dutch and Kenyans are tall does not, in isolation, mean anything apart from the fact that they are both tall. It is a trait that could easily evolve several times, and cannot in isolation be seen as an apomorphic trait for a group including only the Dutch and the Kenyans, unless that is the most parsimonious grouping when you consider all studied taxa and all studied characters.

Having said that, it is perfectly valid to separate taxa based on ranges even if these overlap. In some groups you might do it even if all other characteristics are identical (or virtually identical). Naturally you would try to find other differences as well, but if there are none, then these will have to do.

Are blue-eyed, black-haired Afghans the same race as blue-eyed, blonde Norwegians, or as brown-eyed, black-haired Persians?

They could be neither. There is no way to tell from only two characters, especially since those two characters seem to be quite variable regardless of geographic distribution within the containing taxon.

 

[Dancing David]

No, I think the burden's on you: show me the study that when controlling for group differences in prenatal effects of alcohol, the group difference in IQ goes away.

FWIW, I do think prenatal issues and/or nutrition are likely causes, but I need to see the data. Please post it, if you know of it.

That would be nice but to say that an effect exists without controlling for confounding factors is a valid critique. there is no burden of proof as it a a critique of protocol. If it is not conseidered then it is a potential flaw in methodology. I can show you studies that would indicate that there is an impact from prenatal alcohol exposure on overall functioning and likely IQ.

So it is upon the people who claim an effect to show that they eliminated confounding factors, I can show that prenatal alcohol exposure has an effect.

 

[drkitten]

If I do the same experiments with set of creatures called cats'n'dogs and can't find any distinction, does this prove there are only cogs?

Actually, I think it would prove that you were a lousy biologist.

But it would also prove that height is a lousy way of distinguishing cats from dogs. There are much better ways of distinguishing them, as any mammalogist can tell you, differences that do show distinction -- and that we've been able to tie to genetic differences as well. Just as a simple example, we can distinguish them via dental formula; dogs have 42 teeth, cats 30, and there don't seem to be any non-pathological cases that have 36.

The problem is that we've not been able to find any such distinctive differences among the various "races." If you think you can find an anatomical property that is shared by all and only "blacks," please name it (bearing in mind that "dark skin" won't work for reasons already outlined).

 

[Pup]

I'm obviously not saying that we can't differentiate the color, or shade, of one person's skin from another, or use words to describe the difference. What I'm saying is that the groupings we have created on the basis of skin color are arbitrary, and inaccurate. While it may be apparent that one person is a different color from another, it is not at all apparent that our racial classifications describe visually discrete and distinct groups, as they pretend.

Do you think it was always that way? In other words, there's been a lot of mixing, but 1,000 years ago, let's say, I don't think it would be as arbitrary to pick a person from England, a person from central Africa, a person from Japan and a person from Central America and say they each had certain genetic characteristics typical of the people around them, and that those characteristics would be passed on to their children, and that you could say which continent they came from by looking at them.

As I've said in this thread, we're gradually losing those distinctions and eventually new ones will form based on different kinds of isolation, but I don't think they're totally arbitrary, because different races (or whatever you want to call them) originally appeared based on separate breeding populations.

It would be like walking into a pound and categorizing the mutts into breeds. "That looks like a German shepherd, that might be a schnauzer-poodle cross, that's a spaniel, etc." We might have to guess, we might get it wrong, we might disagree with someone else. But that doesn't mean that such things as German shepherds or spaniels are merely arbitrary classifications. It just means that in the pound, the dogs aren't bred from isolated populations of one type breeding with a similar type for generations. If we went to a breeder's home, we could indeed see "real" German shepherds and have no trouble identifying them.

If one scrapes away all the baggage that "racial purity" has attached to it, seems to me that's all it is. It's not better or worse for a person to have a long line of similar-appearing ancestors, but it does produce a certain biological result, as real as the difference between a German shepherd and a mutt.

 

[Michael Redman]

Having said that, it is perfectly valid to separate taxa based on ranges even if these overlap. In some groups you might do it even if all other characteristics are identical (or virtually identical). Naturally you would try to find other differences as well, but if there are none, then these will have to do.

No one is disputing that for some purposes, people can be grouped together based on common characteristics. And I, at least, am not arguing that these classification are not useful for some purposes. However, the OP is asking about differentiated human races.

The concept of "races" among humans (as indicated by the use of the term race itself) is not the concept that there are populations that can be grouped together based on common characteristics.

The "races" into which humans were historically divide were based more or less on nothing but the landmass the people happened to be living on at the time, and cultural views of the people doing the description. They lumped people together despite displaying vastly differing characteristics, and separated people with similar characteristics on geographical and even political grounds. It was imagined that these groups were, in fact, discrete and distinct races. They are not.

Again, this is not to say that there are not valid and useful ways to differentiate human populations. But assigning all humans a "race" among white/black/yellow/red is neither valid nor useful.

 

[drkitten]

Do you think it was always that way? In other words, there's been a lot of mixing, but 1,000 years ago, let's say, I don't think it would be as arbitrary to pick a person from England, a person from central Africa, a person from Japan and a person from Central America and say they each had certain genetic characteristics typical of the people around them, and that those characteristics would be passed on to their children, and that you could say which continent they came from by looking at them.

The problem is that you're still not able to make useful distinctions. All you're doing is losing the continuum.

Even 1000 years ago, you would still have said that a Japanese person and a Chinese person were 'the same race,' and that an Englishman and a Frenchman were also 'the same race' but a different one from the Japanese.

But how now let's look at the Chinaman against a Mongolian. And the Mongolian against a Siberian. And the Siberian against a Uralian. And the Uralian against a Russian. And a Russian against a Pole, against a German, against that Frenchman.

Where is the "distinction"?

If you're talking about dog breeds, you can identify the specific characteristics -- this is a poodle because ... Tell me again what makes an Englishman "English" or "white"?

 

[Michael Redman]

Do you think it was always that way? In other words, there's been a lot of mixing, but 1,000 years ago, let's say, I don't think it would be as arbitrary to pick a person from England, a person from central Africa, a person from Japan and a person from Central America and say they each had certain genetic characteristics typical of the people around them, and that those characteristics would be passed on to their children, and that you could say which continent they came from by looking at them.

I believe those populations were not as isolated nor for as long as you suggest. People move around a lot. More importantly, they were not as homogenous.

The claim of differentiated human races is that all white people share certain characteristics, and that all asians share different characteristics, etc., not simply that there are some discrete differences between some populations living in different areas.

 

[bpesta22]

That would be nice but to say that an effect exists without controlling for confounding factors is a valid critique. there is no burden of proof as it a a critique of protocol. If it is not conseidered then it is a potential flaw in methodology. I can show you studies that would indicate that there is an impact from prenatal alcohol exposure on overall functioning and likely IQ.

So it is upon the people who claim an effect to show that they eliminated confounding factors, I can show that prenatal alcohol exposure has an effect.

No it's not; I readily admit that alcohol can seriously affect a developing fetus and his/her IQ.

The burden's still on you, because you are claiming alcohol is confounded with race. You need to show not just that alcohol affects iq but that alcohol intake varies systematically across whites and blacks, and when controlled for, explains the 15 point gap in IQ scores.

So, you should start digging up studies showing that pregnant black ladies are more likely to drink despite the risk to kids than are pregnant white ladies. That sounds like a racist thing, what you are asserting there, btw.

 

[Soapy Sam]

Taxonomic rankings are defined by the International Commission on Zoological Nomenclature.

Yes .
Unfortunately, people are not.
Which was the point of the post you responded to.

 

[Perpetual Student]

No it's not; I readily admit that alcohol can seriously affect a developing fetus and his/her IQ.

The burden's still on you, because you are claiming alcohol is confounded with race. You need to show not just that alcohol affects iq but that alcohol intake varies systematically across whites and blacks, and when controlled for, explains the 15 point gap in IQ scores.

So, you should start digging up studies showing that pregnant black ladies are more likely to drink despite the risk to kids than are pregnant white ladies. That sounds like a racist thing, what you are asserting there, btw.

How hard can it be to control for alcoholic intake? Of course, there are quite a few other potentially confounding factors which make studying two populations for all such factors very difficult.

 

[bpesta22]

How hard can it be to control for alcoholic intake? Of course, there are quite a few other potentially confounding factors which make studying two populations for all such factors very difficult.

It's not just "controlling" for alcohol intake. One would have to show statistical mediation or at least attenuation.

The only way alcohol can explain the gap (barring some unknown suppressor variable) is if: black moms drink more than white moms during pregnancy. That difference, when entered into a regression equation, results in the beta weight for race predicting IQ to be zero (or at least statistically less than 15-- the expected difference).

I suppose it's also possible that they drink the same, but perhaps it's worse for one race or another (though that would suggest something biological about race in and of itself).

I had a similar debate on this elsewhere recently. It seems hard to get across the point: there is a difference between a source of error (the effects of alcohol on IQ when one is interested in, say, race/iq differences) versus a confound (when alcohol systematically varies by race). The former is irrelevant to anything but statistical power. The latter I am calling a confound, but if that confound could be found, it would be the factor x in the environment that explains the black-white IQ gap. No one's found it.

 

[Pup]

Where is the "distinction"?

If you're talking about dog breeds, you can identify the specific characteristics -- this is a poodle because ... Tell me again what makes an Englishman "English" or "white"?

I think we're getting into the same old problem of claiming that because there are no sharp divisions, then there must be no divisions at all.

A poodle is a poodle because... there are certain visible characteristics which it has (and perhaps invisible ones as well, such as a herding or hunting instinct in some breeds), which it passes reliably to its offspring if bred with another poodle.

A white person is a white person because... there are certain visible characteristics which he or she has (and perhaps invisible ones as well, but we won't go there), which he or she passes reliably to his or her offspring if bred with another similar person.

I see no difference. I could list the characteristic points for human beings the same as I could for poodles. I could also point to examples of "almost poodles" and "poodle crosses" and "sorta looks vaguely like a poodle but probably wouldn't breed true," just as I could point to "black people" and "mixed-race people" and "sorta looks black but told me he had one Asian parent and one American Indian parent."

But am I really the only person in the world who can tell the difference between people who look like the queen of England and people who look like the Emir of Kano, and also predict that if they have ancestors who look like them, and marry someone who looks like them, they'll also have children who look like them? That's all race means to me. There's no value judgment, neither about what appearance is best nor about whether it's better for a kid to have parents that resemble each other or not.

Of course, there aren't any "breed registries" for people, so it all happens very sloppily and naturally in people, rather than planned breeding to meet a registry standard (thank god). But one can still see similar trends. And if one thinks that dog breeds are nice and neat, one only needs to look at the fights that occur and the constant changes among breeders and breed standards.

So distinctions in humans aren't really "useful"--and honestly, they're not all that "useful" in dogs either, as far as appearance goes, except that we hold dog shows and declare that they are.

But I just can't figure out how to deny what my eyes and common sense tell me, whether it's useful or not.

 

[Pup]

I believe those populations were not as isolated nor for as long as you suggest. People move around a lot. More importantly, they were not as homogenous.

The claim of differentiated human races is that all white people share certain characteristics, and that all asians share different characteristics, etc., not simply that there are some discrete differences between some populations living in different areas.

The claim by who? Personally, I'm not claiming that at all. Maybe that's where the misunderstanding is occurring. I'm claiming it's a bell curve, or more aptly a sine curve, with people who look closest to "black" or "white" or "asian" (or whatever divisions you want) spaced apart with broad areas between where people are impossible to categorize. One could divide it down as far as one wanted--subtypes of whites or blacks or asians, for example.

This is just so obvious, I can't understand how anyone can deny it. I made a trip from the northern U.S. to the southern U.S. on the east coast on a bus recently, and as I progressed farther south, the look of the people changed. The number of straight-haired, light-skinned people with certain types of facial features changed from maybe 80% of the population to maybe 20% of the population. It's happened every time I've travelled.

If it's purely subjective or purely cultural, and not a "real" genetic phenomenon, I'll go for the million dollar challenge: take 20 random people from a bus station in Atlanta and a bus station in Buffalo, dress them in the same clothes with the same hairstyles and don't let me hear their accents or any cultural/voluntary characteristics, and I'll predict 9 times out of 10 which bus station each group of 20 represented from their genetic appearance alone.

 

[Prometheus]

It's not just "controlling" for alcohol intake. One would have to show statistical mediation or at least attenuation.

The only way alcohol can explain the gap (barring some unknown suppressor variable) is if: black moms drink more than white moms during pregnancy. That difference, when entered into a regression equation, results in the beta weight for race predicting IQ to be zero (or at least statistically less than 15-- the expected difference).

I suppose it's also possible that they drink the same, but perhaps it's worse for one race or another (though that would suggest something biological about race in and of itself).

I had a similar debate on this elsewhere recently. It seems hard to get across the point: there is a difference between a source of error (the effects of alcohol on IQ when one is interested in, say, race/iq differences) versus a confound (when alcohol systematically varies by race). The former is irrelevant to anything but statistical power. The latter I am calling a confound, but if that confound could be found, it would be the factor x in the environment that explains the black-white IQ gap. No one's found it.

What does the IQ data look like for people who are identified as bi-racial?

 

[bpesta22]

What does the IQ data look like for people who are identified as bi-racial?

Surprisingly (or go figure) about half way in between. The gap is 15 points black versus white, and about half that for bi-racial black/white. I remember reading it's better predicted by the mother's race than the fathers, but I could be making that up / can't find a cite.