Humans have not stopped evolving, and races biologically exist

[Togo]

As Juma points out, Phenotype and Genotype are alternatives bases for classification.

And that's where it breaks down. You guys evidently take it for granted that phenotypical groupings and genetic groupings are mutually exclusive.

No, we don't. That's why both we and Mayr described the phenotype groupings as having common genetic traits.

You are arguing that Mayr says race isn't a genetic grouping.

Because it isn't. The identifier for group membership is phenotype, not genotype. That doesn't mean they can't be genetically similar, but it does mean they may not be. People are not going around doing DNA tests on all and sundary and then putting them into groups on that basis. They're grouping based on what they look like, and then looking for genetic similiarities within those groups.

He clearly states that these are phenotypical groups, and then goes on to suggest that some of thes groups may have a few traits that indicate some kind of common genetic basis.

That is a reading colored by the preconceptions you're bringing to bear.

<shrug> It's literally what he says.

He clearly states that each of these groups definitely has a common genetic basis: "A human race consists of the descendants of a once-isolated geographical population primarily adapted for the environmental conditions of their original home country." That is all it takes to be a genetic group.

No it isn't. If your initial population is diverse, then your geographically isoloated population will stay diverse. If your intial population is highly homogenuous, then it will stay that way. All geographic isolation does is stop further mixing with outgroups.

The point he's making is again about phenotype. A particular set of enviromental conditions will encourage phenotype to develop in a particular way. Hot sun leads to darker skin, for example. It doesn't follow from that all people with dark skin have the same genes.

For example, look at the Galopagus finches, one of the most famous case studies in evolutionary science. They adapted their phenotype to exploit a wide variety of ecological niches that in the rest of the world were filled with other species. That doesn't mean that every bird that pecks at tree bark is a woodpecker, nor does it mean that all birds with woodpecker-style beaks are related in any way whatsoever, even though they look similar. By the same token, 'Blacks' are not a genetic group, and even black people with very dark skin come from a great range of different areas, at different times, and have very different genes. They may look similar to eachother, because they have a similar phenotype, because they have similar enviromental conditions in their heritage, but they're not any more closesly related to eachother than they would be to a European.

So when you see people with the same phenotype, there are two possible evolutionary explanations
a) They are interrelated, and genetically similar
b) They are not related, but in their evolutionary history, they both come from genetically different groups that experienced similar evolutionary pressures.

When Mayr defines a race as "differing taxonomically from other populations of that species", that means he's defining it as a genetic group.

No. Taxonomy means 'classification by characteristics'. Yes, in modern science creatures are classfiied by evolutionary characteristics, but in the context of what he's saying he's still talking about phenotype. That's why he claims in the next sentance that the fact that races exist can't be denied, irrespective of the causes of those differences. He's saying, quite sensibly, that in every species there are obvious differences based on geopgraphy

But the groups are not genetic groups, they are phenotypical groups. Races are phenotypes - they're based on appearance.

The whole reason phenotypes group naturally into the groups we observe is because they're also genetic groups -- the descendants of once-isolated geographical populations.

Sure, there are traits that the phenotype has that those not in the group clearly do not have. But it doesn't follow from that the group is a genetic group, because the genes, and the evolutionary routes by which they arose, that each member of the phenotype group has, could be very different.

Race identification used to be based on appearance, because that was all anthropologists had to go on and they did the best they could; but from the get-go that was understood to be a procedure for recognizing relatedness. Now that we can measure genetic distance, who the heck still classifies Polynesians as Caucasoid?

But now we can measure relatedness, we can recongise that the racial groups we're used to using are not, in fact, coherant genetic groups. As measured by comparing the variation within the group to the variation between groups.

Now you may want to suggest that there exist invisible racial distinctions that don't correspond to the racial groups we usually use. That it might be possible to draw a circle around various hereditary groups and identify genes they have in common, even though they don't look particularly similar. But why would this matter?

 

[fromderinside]

I agree with most of those points, though, regardless of what Mayr thinks or what you think he thinks, I think the facts and theory are plain that race is both phenotypic and genotypic.

I know you do. And I think that the facts come out disagreeing with that position.

It's worth reviewing the principle objections to what you believe is plain.

For instance, the point about comparing between groups to within group is a statistical point about what makes a coherant grouping. You can draw a circle around any set of data points and call it a group. And in any such group you'll tend to find some genes are more common than others, whether that groups has coherant features, or whether it was chosen entirely at random. So when social scientists look at a group, one of the things they look for is some kind of unifying correlate - something that tends to be true of members within the group but not of members outside the group. The best measure of this is a comparison between differences within the group and differences between that group and other groups. If the differences within the group are very large, and the differences between groups are compartively small, then the feature you are measuring is not a defining factor of group membership - that is that people, considering that factor alone, do not in fact fall into measureable groupings. It's not a complaint about the weakeness of the correlation, or the unusefulness of the measure - it's a statistical finding that for that feature, people do not in fact fall into these groupings.

Took a while.

 

[fromderinside]

But the groups are not genetic groups, they are phenotypical groups. Races are phenotypes - they're based on appearance.

The whole reason phenotypes group naturally into the groups we observe is because they're also genetic groups -- the descendants of once-isolated geographical populations. Race identification used to be based on appearance, because that was all anthropologists had to go on and they did the best they could; but from the get-go that was understood to be a procedure for recognizing relatedness. Now that we can measure genetic distance, who the heck still classifies Polynesians as Caucasoid?

The fact that appearance continues when phenotpical races are inbred is that a few genes continue to be expressed. Observation of a phenotypical race does not follow that there must also be genotypical race. What seems to be happening in places where phenotypical races are cross mating? Why you're seeing a convergence of what seemed to be races into a what appears to be a single race with a bit of variability. In america and particularly Hawaii we're seeing browning of humanity. Tey Sachs on the other hand is slowly disappearing whilst type I Diabetes is on the rise. Those latter two should demonstrate to all that phenotype doesn't mean genotype must follow. It comes down to genetic probabilities with the potential for carrying through significant phenotypic attributes in the gene pool.

 

[ApostateAbe]

In response to Togo et al: you can get your DNA tested at 23andMe.com, and the test will tell you, based on the DNA sample alone, what "geographic ancestry" (aka race) you belong to, with high probability. It works, because geneticists have thoroughly mapped varying allele frequencies to "ethnic groups" (aka races). This Wikipedia page gives a table of ethnic groups and haplogroups:

http://en.m.wikipedia.org/wiki/Y-DNA_haplogroups_by_ethnic_group

This genetic identification of race is used very effectively in the criminal justice system, to either confirm or exonerate suspects.

It would not be possible if racial categories had no biological basis. The popular claim of no biological basis of race (backed by scientific authorities on TV screens) was justified by the Continuum Fallacy (continuous therefore subjective) and by Lewontin's Fallacy (greater variation within groups than between groups therefore no meaningful differences between groups). Those arguments should now appear patently ridiculous, like believing the Earth is flat while looking at it from the Moon.

 

[Togo]

In response to Togo et al: you can get your DNA tested at 23andMe.com, and the test will tell you, based on the DNA sample alone, what "geographic ancestry" (aka race) you belong to, with high probability. It works, because geneticists have thoroughly mapped varying allele frequencies to "ethnic groups" (aka races).

Indeed so. And if you send your birthdate to almost any astrologer in the world, they will be able to tell you, based on birthdate alone, what 'star sign' you belong to. It works, because astrologers have thoroughly mapped the various birth dates to various periods of the year (aka 'star signs'). That doesn't, in itself, tell you whether grouping birthdates like this is actually meaningful, or whether people with a birthdate in a particular group have similar influences on their personality.

...and by Lewontin's Fallacy (greater variation within groups than between groups therefore no meaningful differences between groups). Those arguments should now appear patently ridiculous, like believing the Earth is flat while looking at it from the Moon.

Again, many scientists in the field appear to disagree. If you read the the page of Lewontin's Fallacy that you cited, and particularly the section entitled 'responses' to Edwards, you'll see various arguements that have already been made in this thread. I founds Witherspoon's comments particularly interesting.

I'd note also that 'Lewontin's Falllacy' is a misnomer - it's an example of an instance fallacious reasoning, rather than a logical fallcy in it's own right. In this case, Lewontin, writing in the 1970s, pointed out that people of the same race don't tend to have the same genes. The 'fallacy' was that people of the same race tend to have a similar probability of gene clusters, a point which his research didn't test for. That doesn't answer the within-groups between-groups variation problem, nor it is entirely clear whether this probability clustering is sufficient to argue for differences in expression. And there's still a lack of a strong link between race by geographic ancestory and race by genetic clustering, and between those and race by phenotype, which is still how the term is most commonly used and understood.

- - - Updated - - -

Took a while.

...but we finally found something we agree on!

 

[ApostateAbe]

Indeed so. And if you send your birthdate to almost any astrologer in the world, they will be able to tell you, based on birthdate alone, what 'star sign' you belong to. It works, because astrologers have thoroughly mapped the various birth dates to various periods of the year (aka 'star signs'). That doesn't, in itself, tell you whether grouping birthdates like this is actually meaningful, or whether people with a birthdate in a particular group have similar influences on their personality.

...and by Lewontin's Fallacy (greater variation within groups than between groups therefore no meaningful differences between groups). Those arguments should now appear patently ridiculous, like believing the Earth is flat while looking at it from the Moon.

Again, many scientists in the field appear to disagree. If you read the the page of Lewontin's Fallacy that you cited, and particularly the section entitled 'responses' to Edwards, you'll see various arguements that have already been made in this thread. I founds Witherspoon's comments particularly interesting.

I'd note also that 'Lewontin's Falllacy' is a misnomer - it's an example of an instance fallacious reasoning, rather than a logical fallcy in it's own right. In this case, Lewontin, writing in the 1970s, pointed out that people of the same race don't tend to have the same genes. The 'fallacy' was that people of the same race tend to have a similar probability of gene clusters, a point which his research didn't test for. That doesn't answer the within-groups between-groups variation problem, nor it is entirely clear whether this probability clustering is sufficient to argue for differences in expression. And there's still a lack of a strong link between race by geographic ancestory and race by genetic clustering, and between those and race by phenotype, which is still how the term is most commonly used and understood.

- - - Updated - - -

Took a while.

...but we finally found something we agree on!

See the study by Tang et al: "Genetic Structure, Self-Identified Race Ethnicity, and Confounding in Case-Control Association Studies." Assuming four race clusters, over 99.8% of 3000 subjects accurately self-identified their own race against genetic testing. Togo, this is not astrology. This is astronomy. I had my DNA tested by 23andMe.com. They said I had 100% European ancestry. They could have said I had 100% Polynesian ancestry. And I would be taking a very long look in the mirror. Astrology? Seriously?

 

[fromderinside]

See the study by Tang et al: "Genetic Structure, Self-Identified Race Ethnicity, and Confounding in Case-Control Association Studies." Assuming four race clusters, over 99.8% of 3000 subjects accurately self-identified their own race against genetic testing. Togo, this is not astrology. ... Astrology? Seriously?

You wrote it yourself. Self identified race identity. Phenotypology not genotypology.
Astrology not Astronomy. Seriously. Its a bit like form follows function, a nice advertising catch slogan but no cigar.

 

[Bomb#20]

As Juma points out, Phenotype and Genotype are alternatives bases for classification.

And that's where it breaks down. You guys evidently take it for granted that phenotypical groupings and genetic groupings are mutually exclusive.

No, we don't. That's why both we and Mayr described the phenotype groupings as having common genetic traits.

That's a strange response. Are you equating "having common genetic traits" with "genetic grouping"?

If you ARE equating them, then we're done: you've just conceded that I'm right and you're wrong. If you recall, you started this dispute by claiming in post #92 "it also reinforces the points that critics of 'genetic races' consistently make - that race is a phenological grouping, and not a genetic one". That's what you said that I'm arguing with you about. So if you equate "having common genetic traits" with "genetic grouping" and you grant that Mayr described races as having common genetic traits, then you've granted that Mayr does not in point of fact reinforce the critics' point that race isn't a genetic grouping.

Contrariwise, if you ARE NOT equating "having common genetic traits" with "genetic grouping", then your above answer to me is unresponsive. Instead of addressing my observation -- that calling phenotype and genotype "alternatives" takes for granted that they're mutually exclusive -- you're simply changing the subject from "genetic grouping" to "having common genetic traits".

You are arguing that Mayr says race isn't a genetic grouping.

Because it isn't. The identifier for group membership is phenotype, not genotype. That doesn't mean they can't be genetically similar, but it does mean they may not be.

That's your brain you're talking about. You think the identifier is phenotype, not genotype. You think members of the same group may not be genetically similar. So what? Neither the fact of the matter nor your opinion about it is the point in dispute. Your claim was that Mayr reinforces that opinion. So you need to produce evidence that Mayr implied the identifier is phenotype only, as opposed to both, and implied members of the same group may not be genetically similar.

People are not going around doing DNA tests on all and sundary and then putting them into groups on that basis. They're grouping based on what they look like, and then looking for genetic similiarities within those groups.

Actually, going around doing DNA tests on all and sundry and then putting them into groups on that basis is precisely what a number of researchers are doing; but if you want to argue the facts of genome research, we should move it over to the Natural Science forum.

He clearly states that these are phenotypical groups, and then goes on to suggest that some of thes groups may have a few traits that indicate some kind of common genetic basis.

That is a reading colored by the preconceptions you're bringing to bear.

<shrug> It's literally what he says.

Quote him.

He clearly states that each of these groups definitely has a common genetic basis: "A human race consists of the descendants of a once-isolated geographical population primarily adapted for the environmental conditions of their original home country." That is all it takes to be a genetic group.

No it isn't. If your initial population is diverse, then your geographically isoloated population will stay diverse. If your intial population is highly homogenuous, then it will stay that way. All geographic isolation does is stop further mixing with outgroups.

Not true -- it also shuffles the initial genes together. Earlier you wrote:

"The best measure of this is a comparison between differences within the group and differences between that group and other groups. If the differences within the group are very large, and the differences between groups are compartively small, then the feature you are measuring is not a defining factor of group membership - that is that people, considering that factor alone, do not in fact fall into measureable groupings."​

What this analysis with it's repeated use of the singular evidently misses is that when races are identified by grouping phenotypes, it isn't done by considering one feature or one factor alone. That's an error that critics of 'genetic races' consistently make. They jump from the premise that within-group differences in one factor being larger than between-group differences means people do not in fact fall into measureable groupings based on that factor alone, to the conclusion that within-group differences in many factors being larger than between-group differences means people do not in fact fall into measureable groupings based on those factors collectively. But that's an invalid inference. Critics jump to that conclusion by pattern matching rather than by using mathematical reasoning. In fact if there are even only two factors, that may well be enough for the people to fall into measurable groupings even though within-group differences are larger than between-group differences for both factors. And as the number of different factors rises this effect only gets stronger. The clustering doesn't lie in the specific values of each factor you measure, but in the pattern of correlations among them. And all that shuffling of genes that goes on during the centuries the descendants of the initial population are isolated massively increases the correlations among all those diverse genes.

The point he's making is again about phenotype. A particular set of enviromental conditions will encourage phenotype to develop in a particular way. Hot sun leads to darker skin, for example. It doesn't follow from that all people with dark skin have the same genes.
...
That doesn't mean that every bird that pecks at tree bark is a woodpecker, nor does it mean that all birds with woodpecker-style beaks are related in any way whatsoever, even though they look similar. By the same token, 'Blacks' are not a genetic group, and even black people with very dark skin come from a great range of different areas, at different times, and have very different genes.

Excellent example. Let's talk about it. There was a popular expression in the 60s and 70s, back before the modern explosion of protected groups. What you weren't allowed to discriminate on the basis of was "race, creed or color". Are you old enough to remember that saying?

The point is, "Black" is not a race. It's a color. And fifty years ago when, there was no genetic testing to speak of besides ABO blood groups, we already knew perfectly well that race and color are two different things.

They may look similar to eachother, because they have a similar phenotype, because they have similar enviromental conditions in their heritage, but they're not any more closesly related to eachother than they would be to a European.

Yes. That's exactly right. And that's precisely why 'Blacks' are not a race. We didn't need genetic testing to know Australian Aborigines aren't from the same race as Ghanaians; the reason we didn't need genetic testing is because phenotypic features are effective as a stand-in for genetic grouping when you use enough of them; and we used enough of them. The phenotypes Mayr is talking about when he talks about phenotypic similarity are large sets of features. He is not talking about grouping 'Blacks' and calling that a "race".

So when you see people with the same phenotype, there are two possible evolutionary explanations
a) They are interrelated, and genetically similar
b) They are not related, but in their evolutionary history, they both come from genetically different groups that experienced similar evolutionary pressures.

But you never see people with the same phenotype -- no two people have the same phenotype. To talk of people having the same phenotype is to choose to ignore all features of their phenotypes except those you're interested in at the moment. When two people have a feature of their phenotypes in common, there are two possible evolutionary explanations. The more features they have in common, the more likely they are to be related and the less likely it is for each of the shared features to have been coincidentally pushed in the same direction by independent evolutionary pressures. Convergent evolution often creates superficial resemblance; it never creates detailed correspondence across a wide range of features.

When Mayr defines a race as "differing taxonomically from other populations of that species", that means he's defining it as a genetic group.

No. Taxonomy means 'classification by characteristics'. Yes, in modern science creatures are classfiied by evolutionary characteristics, but in the context of what he's saying he's still talking about phenotype. That's why he claims in the next sentance that the fact that races exist can't be denied, irrespective of the causes of those differences. He's saying, quite sensibly, that in every species there are obvious differences based on geopgraphy

So your theory is that one of the most famous and respected evolutionary biologists of the 20th century decided to revert to pre-Darwinian systematics, just for this one case?

But the groups are not genetic groups, they are phenotypical groups. Races are phenotypes - they're based on appearance.

The whole reason phenotypes group naturally into the groups we observe is because they're also genetic groups -- the descendants of once-isolated geographical populations.

Sure, there are traits that the phenotype has that those not in the group clearly do not have. But it doesn't follow from that the group is a genetic group, because the genes, and the evolutionary routes by which they arose, that each member of the phenotype group has, could be very different.

"It doesn't follow", you say. I.e., it is in principle possible to choose a set of features and divide people into phenotypical groups based on that set in such a way that the grouping does not correspond to relatedness and common evolutionary history. True. But what reason do you have to think Mayr believes this may be what happened in the case of human races? "A human race consists of the descendants of a once-isolated geographical population primarily adapted for the environmental conditions of their original home country."

Devising techniques to allow us to distinguish between "analogy" and "homology", i.e. to recognize whether a particular phenotypical grouping reflects very different genes and very different evolutionary routes, or reflects a corresponding genetic grouping, is the underlying strategy of post-1859 taxonomy. When biologists figure out that a proposed grouping is non-genetic, they discard it.

Race identification used to be based on appearance, because that was all anthropologists had to go on and they did the best they could; but from the get-go that was understood to be a procedure for recognizing relatedness. Now that we can measure genetic distance, who the heck still classifies Polynesians as Caucasoid?

But now we can measure relatedness, we can recongise that the racial groups we're used to using are not, in fact, coherant genetic groups.

So you are of the opinion that Caucasoids, for example, aren't a coherent genetic group. Believe what you like. Do you have reason to think Mayr agrees with you?

As measured by comparing the variation within the group to the variation between groups.

See above. Races are clusters of similarity across many, many features. Intuition about one-dimensional figures is a poor guide to hundred dimensional geometry.

Now you may want to suggest that there exist invisible racial distinctions that don't correspond to the racial groups we usually use. That it might be possible to draw a circle around various hereditary groups and identify genes they have in common, even though they don't look particularly similar. But why would this matter?

Why would I want to suggest such a thing, when I could instead suggest that it is possible to draw a circle around various hereditary groups, not by cherry-picking a few genes they have in common but by selecting hundreds of SNPs at random, and observe that they're visible, they do look particularly similar, and they do correspond to racial groups anthropologists usually used before that sort of thing became unfashionable? You appear to be inviting me to surrender when your army is surrounded and out of ammunition.

Now you may want to suggest that those racial groups are unusual and/or don't count as visible, on account of you being surrounded by English neighbors who think of your Pakistani neighbors as Asian rather than as Caucasian. That might make for an interesting discussion of the difference between social and biological race and of how out of touch the general public tend to be with what's long been known to experts. But that hardly makes racial distinctions anthropologists recognized visually invisible; nor does it mean Mayr is claiming races aren't genetic groupings.

 

[Togo]

As Juma points out, Phenotype and Genotype are alternatives bases for classification.

And that's where it breaks down. You guys evidently take it for granted that phenotypical groupings and genetic groupings are mutually exclusive.

No, we don't. That's why both we and Mayr described the phenotype groupings as having common genetic traits.

That's a strange response. Are you equating "having common genetic traits" with "genetic grouping"?

No.

Contrariwise, if you ARE NOT equating "having common genetic traits" with "genetic grouping", then your above answer to me is unresponsive. Instead of addressing my observation -- that calling phenotype and genotype "alternatives" takes for granted that they're mutually exclusive -- you're simply changing the subject from "genetic grouping" to "having common genetic traits".

I'm disagreeing with your observation. That they are alternative measures does not make them mutually exclusive.

You are arguing that Mayr says race isn't a genetic grouping.

Because it isn't. The identifier for group membership is phenotype, not genotype. That doesn't mean they can't be genetically similar, but it does mean they may not be.

That's your brain you're talking about. You think the identifier is phenotype, not genotype.

So does Myr. That's why he's using the term phenotype, and not the term genotype.

You think members of the same group may not be genetically similar. So what?

No, missing the point. The point is that a phenotype group does not in itself imply a genetic group. There may well be a genetic group, but you can't tell from the fact of the phenotype.

Your claim was that Mayr reinforces that opinion. So you need to produce evidence that Mayr implied the identifier is phenotype only, as opposed to both, and implied members of the same group may not be genetically similar.

His article addresses phenotype groups, and he discusses whether or not they are genetically similar. Neither he nor anyone else here is arguing that a phenotype somehow stops things being genetically related.

[

People are not going around doing DNA tests on all and sundary and then putting them into groups on that basis. They're grouping based on what they look like, and then looking for genetic similiarities within those groups.

Actually, going around doing DNA tests on all and sundry and then putting them into groups on that basis is precisely what a number of researchers are doing; but if you want to argue the facts of genome research, we should move it over to the Natural Science forum.

Great, cite of that research and we can discuss. It's probably more pertinent.

What this analysis with it's repeated use of the singular evidently misses...

The quotes comes from an earlier point in the conversation before the distinction between single factor and cluster analysis was made.

Critics jump to that conclusion by pattern matching rather than by using mathematical reasoning.

If you say so. The points I'm making are from the viewpoint of the perils of using clusters of results in the absence of a actual definition. If you grab any old data, and run it through a multivariate analysis, you'll get groups in the results, as long as you have a large enough data set and enough potential dimensions. The mathematical error is to assume that because you can draw a line around a cluster of results, the cluster must somehow be a meaningful group. Hence the astrology comparison. People can be sorted into groups by star signs, but that doesn't in itself make start signs 'real' or meaningful in any way. Similarly, the fact that you can identify a group of people by common genetic markers does not in itself make that grouping useful or significant.

The point he's making is again about phenotype. A particular set of enviromental conditions will encourage phenotype to develop in a particular way. Hot sun leads to darker skin, for example. It doesn't follow from that all people with dark skin have the same genes.
...
That doesn't mean that every bird that pecks at tree bark is a woodpecker, nor does it mean that all birds with woodpecker-style beaks are related in any way whatsoever, even though they look similar. By the same token, 'Blacks' are not a genetic group, and even black people with very dark skin come from a great range of different areas, at different times, and have very different genes.

Excellent example. Let's talk about it. There was a popular expression in the 60s and 70s, back before the modern explosion of protected groups. What you weren't allowed to discriminate on the basis of was "race, creed or color". Are you old enough to remember that saying?

The point is, "Black" is not a race. It's a color. And fifty years ago when, there was no genetic testing to speak of besides ABO blood groups, we already knew perfectly well that race and color are two different things.

Ok, so when you say 'races biologically exist', what you mean is that:
1) People have genes
2) These genes occur in correlational clusters
3) People with similar patterns of clustering can be labelled as belonging to 'races'
4) These races may not bear any relationship whatsoever to races as the term is commonly understood
5) These races may not have any common traits beyond those clusters

[

So when you see people with the same phenotype, there are two possible evolutionary explanations
a) They are interrelated, and genetically similar
b) They are not related, but in their evolutionary history, they both come from genetically different groups that experienced similar evolutionary pressures.

But you never see people with the same phenotype -- no two people have the same phenotype.

Or indeed genotype. Just use similar throughout if the distinction bothers you.

Convergent evolution often creates superficial resemblance; it never creates detailed correspondence across a wide range of features.

It doesn't? What about creatures like the Thylacine?
http://en.wikipedia.org/wiki/Thylacine

Now you may want to suggest that there exist invisible racial distinctions that don't correspond to the racial groups we usually use. That it might be possible to draw a circle around various hereditary groups and identify genes they have in common, even though they don't look particularly similar. But why would this matter?

Why would I want to suggest such a thing, when I could instead suggest that it is possible to draw a circle around various hereditary groups, not by cherry-picking a few genes they have in common but by selecting hundreds of SNPs at random, and observe that they're visible, they do look particularly similar, and they do correspond to racial groups anthropologists usually used before that sort of thing became unfashionable?

Cite please.

 

[Bomb#20]

Contrariwise, if you ARE NOT equating "having common genetic traits" with "genetic grouping", then your above answer to me is unresponsive. Instead of addressing my observation -- that calling phenotype and genotype "alternatives" takes for granted that they're mutually exclusive -- you're simply changing the subject from "genetic grouping" to "having common genetic traits".

I'm disagreeing with your observation. That they are alternative measures does not make them mutually exclusive.

In which case, why did you tell me in post #95 that they were alternatives as though that were an argument for your conclusion: "But the groups are not genetic groups, they are phenotypical groups." Since you're saying alternatives can both be true, why can't the groups be simultaneously genetic groups and phenotypical groups? What grounds do you have for thinking Mayr was saying "that race is a phenological grouping, and not a genetic one", rather than saying that race is a phenotypical grouping in addition to being a genetic one?

That's your brain you're talking about. You think the identifier is phenotype, not genotype.

So does Myr. That's why he's using the term phenotype, and not the term genotype.

So what? He uses the terms "differing taxonomically" and "descendants of a once-isolated geographical population." Those imply genotype groupings.

You think members of the same group may not be genetically similar. So what?

No, missing the point. The point is that a phenotype group does not in itself imply a genetic group. There may well be a genetic group, but you can't tell from the fact of the phenotype.

Yeah, I got that point. And it's true. So what? It doesn't provide any logical support for your contention. All it shows is that we cannot infer, from only the fact that Mayr said it's a phenotype group, that he also thinks it's a genotype group. In the first place, that would hardly imply that he thinks it isn't a genotype group; it simply gives no information on that point. And in the second place, it doesn't change the fact that "it's a phenotype group" isn't the only thing Mayr said on the subject. He said other things that imply he thinks it's also a genotype group.

There are a million ways to divide a species into phenotype groups. Most of them are phenotype groups but not genotype groups. Some of them are both phenotype groups and genotype groups. You can't tell one way or the other just from the fact that they're phenotype groups. The groups that are the descendants of once-isolated populations are genotype groups. That's what makes them differ taxonomically, when one uses post-1859 taxonomic principles.

Your claim was that Mayr reinforces that opinion. So you need to produce evidence that Mayr implied the identifier is phenotype only, as opposed to both, and implied members of the same group may not be genetically similar.

His article addresses phenotype groups, and he discusses whether or not they are genetically similar. Neither he nor anyone else here is arguing that a phenotype somehow stops things being genetically related.

No one here argued that anyone here is arguing that. I think you must have misinterpreted my sentence. Unfortunately English has three meanings for the phrase "may not". When I wrote "may not be", you appear to have read that as meaning "can't be" instead of reading it as meaning "might not be". I meant "might not be". You had written "That doesn't mean they can't be genetically similar, but it does mean they may not be."; that's where I got the construction "may not be" from. And you evidently didn't mean "can't be".

The point is, you appeared to jump from the premise that members of a phenotypical group might not be genetically similar to the conclusion that Mayr thinks members of a race might not be genetically similar. That's not a valid inference. A race isn't just any old phenotypical grouping; it's a phenotypical grouping with the additional properties of differing taxonomically from other populations and descending from a once-isolated population. So you'd need to either produce a direct quote, or else show that members of a group that differs taxonomically might not be genetically similar and that the descendants of a once-isolated population might not be genetically similar, in order to conclude that it's likely that Mayr thinks members of the same race might not be genetically similar.

People are not going around doing DNA tests on all and sundary and then putting them into groups on that basis. They're grouping based on what they look like, and then looking for genetic similiarities within those groups.

Actually, going around doing DNA tests on all and sundry and then putting them into groups on that basis is precisely what a number of researchers are doing; but if you want to argue the facts of genome research, we should move it over to the Natural Science forum.

Great, cite of that research and we can discuss. It's probably more pertinent.

Not really on-topic in this forum. But you and the discussion are evidently not to be moved. So I'll quote what I wrote on FRDB the last time I had this debate.

One commonly used measure of genetic distance is called "Fixation Index" or "F_ST". It's a statistical formula that maps the frequencies of a collection of particular genes in people from two populations into an overall measurement of how different the two gene pools are. Dr. Cavalli-Sforza's team computed fixation indices pairwise for forty-two populations, based on published data about 120 genes. They used a computer to analyze the raw genetic distances and identify the best-fitting tree structure. And one of the subtrees in the resulting tree contained all their European sampled populations (including Lapps, Greeks, Basques, etc.), as well as samples from Iran, the Middle East, North Africa, and two samples from India. The genetic distances were 0.05 or less; the minimum genetic distance to other nodes in the tree was 0.11. In short, the computer recognized what is almost the exact category called "Caucasoid" in traditional pre-PC physical anthropology. How did this happen, if there's no such thing as a biological Caucasian? Coincidence? Social constructs exist only in the brains of human beings. Does the Fixation Index formula mathematically read their minds?

Now, let's not overstate the case here. After all, it's not obvious that Fixation Index is the best way to measure genetic distance. There are bound to be aspects of relationship between populations that aren't captured by that math formula. So maybe some other distance metric should have been used. Cavalli-Sforza also computed distances using a different standard formula for calculating genetic distances, the "Nei distance". This resulted in a different pairwise distance table, and a moderately different tree. However, the tree derived from Nei distances did contain a subtree consisting of exactly the same populations as the Caucasian subtree in the fixation index tree.

Anyone claiming "Caucasian" is a social construct resulting from drawing arbitrary lines across a featureless terrain of human genetic variation has an awful lot of explaining to do.

(Source: The History and Geography of Human Genes, Luigi Luca Cavalli-Sforza et al.)

If you say so. The points I'm making are from the viewpoint of the perils of using clusters of results in the absence of a actual definition. If you grab any old data, and run it through a multivariate analysis, you'll get groups in the results, as long as you have a large enough data set and enough potential dimensions. The mathematical error is to assume that because you can draw a line around a cluster of results, the cluster must somehow be a meaningful group. Hence the astrology comparison. People can be sorted into groups by star signs, but that doesn't in itself make start signs 'real' or meaningful in any way. Similarly, the fact that you can identify a group of people by common genetic markers does not in itself make that grouping useful or significant.

Hey, I didn't claim grouping people into races is useful. It would be nice if we all cared no more about one another's race than we do about one another's ear wax type.

But as to meaningfulness and significance: the difference between grouping stars by finding clusters in their two-dimensional positions on the celestial sphere and grouping people by finding clusters in their hundred-dimensional positions on a hundred phenotypical and/or genotypical axes is that the former has no predictive power and the latter does. Whether a star is two-dimensionally in Pisces or in Ursa Minor tells us nothing about its position in the third dimension: how far away it is. If instead we take a chart of stars' parallaxes and right ascensions and look for clusters, we'll find a completely different set of clusters and define groups with no correlation to traditional constellations; and we'll find those clusters have no power to predict their members' declinations.

But people are not stars. Except for a few special clusters like the Pleiades, the clustering in the sky is random. Not so, the clustering in multivariate analyses of phenotypical and genotypical features. Positions along those dimensions cluster the specific way they do because of mankind's history of breaking up into isolated populations. If you repeat your multivariate analysis in a different space, with a different hundred axes measuring a different hundred genes and phenotypical features, you'll get pretty much the same clusters, because there's only one history of who was making babies with whom, and that history created both clustering patterns.

Excellent example. Let's talk about it. There was a popular expression in the 60s and 70s, back before the modern explosion of protected groups. What you weren't allowed to discriminate on the basis of was "race, creed or color". Are you old enough to remember that saying?

The point is, "Black" is not a race. It's a color. And fifty years ago when, there was no genetic testing to speak of besides ABO blood groups, we already knew perfectly well that race and color are two different things.

Ok, so when you say 'races biologically exist', what you mean is that:
1) People have genes
2) These genes occur in correlational clusters
3) People with similar patterns of clustering can be labelled as belonging to 'races'
4) These races may not bear any relationship whatsoever to races as the term is commonly understood
5) These races may not have any common traits beyond those clusters

That's not a reasonable interpretation of what I wrote. You cannot plausibly believe that's what I mean. So you are trying to make some sarcastic point. I assume your point is that if I don't recognize "Black" as a race it means I'm using the word "race" in some novel technical sense that would be unrecognizable to the man on the street, and therefore what I'm saying has no implications for the reality of races as commonly understood. Is that what you're getting at?

Assuming that's what you mean, you're very wrong. If the groups Cavalli-Sforza's computer constructed out of gene frequency data in the 1990s had turned out to be totally different groups from the groups 1960s-era anthropologists called "races", then you'd have a valid point. But that's not what happened. What happened is his data showed "Caucasoid", "Negroid" and "Mongoloid" correspond to natural features of the human gene pool. That looks to me like a relationship to races as the term is commonly understood. If that doesn't look to you like a relationship to races as the term is commonly understood, why doesn't it look that way to you? Because some of the men on the street are so ignorant they think an Australian Aborigine is a "Negro"? That is not a good reason.

So, to correct your attempted paraphrase point-by-point,

3) People with similar patterns of clustering can be labeled as belonging to races provided we input enough genes into our clustering algorithm and provided we're talking about clusters that are major fractions of H. sapiens; the set of inbred inhabitants of one West Virginia hollow aren't what anyone means by "race";

4) These races are pretty much the conventional races, as the term was commonly understood, by educated people, before ideological race-denialism spread disinformation about the topic;

and 5) These races invariably have millions of common traits beyond the genes that were used to identify the clusters.

Convergent evolution often creates superficial resemblance; it never creates detailed correspondence across a wide range of features.

It doesn't? What about creatures like the Thylacine?
http://en.wikipedia.org/wiki/Thylacine

You mean the Tasmanian Tiger? It didn't look much like a tiger at all except for being striped, so I take it you're comparing it to the wolf. That's a superficial resemblance. Detailed correspondence would be coming from a placenta instead of a pouch, peeing through its penis like a wolf instead of peeing through its butt like a kangaroo, and so forth.

Now you may want to suggest that there exist invisible racial distinctions that don't correspond to the racial groups we usually use. That it might be possible to draw a circle around various hereditary groups and identify genes they have in common, even though they don't look particularly similar. But why would this matter?

Why would I want to suggest such a thing, when I could instead suggest that it is possible to draw a circle around various hereditary groups, not by cherry-picking a few genes they have in common but by selecting hundreds of SNPs at random, and observe that they're visible, they do look particularly similar, and they do correspond to racial groups anthropologists usually used before that sort of thing became unfashionable?

Cite please.

Cited above.

 

[Togo]

I'm disagreeing with your observation. That they are alternative measures does not make them mutually exclusive.

In which case, why did you tell me in post #95 that they were alternatives as though that were an argument for your conclusion: "But the groups are not genetic groups, they are phenotypical groups." Since you're saying alternatives can both be true, why can't the groups be simultaneously genetic groups and phenotypical groups? What grounds do you have for thinking Mayr was saying "that race is a phenological grouping, and not a genetic one", rather than saying that race is a phenotypical grouping in addition to being a genetic one?

That's your brain you're talking about. You think the identifier is phenotype, not genotype.

So does Myr. That's why he's using the term phenotype, and not the term genotype.

So what? He uses the terms "differing taxonomically" and "descendants of a once-isolated geographical population." Those imply genotype groupings.

I'm sure they do, but he's still taking a group that is identified as a phenotype and then discussing whether they may also be related genetically. Hence the identifier is a phenotype.

You think members of the same group may not be genetically similar. So what?

No, missing the point. The point is that a phenotype group does not in itself imply a genetic group. There may well be a genetic group, but you can't tell from the fact of the phenotype.

Yeah, I got that point. And it's true. So what? It doesn't provide any logical support for your contention. All it shows is that we cannot infer, from only the fact that Mayr said it's a phenotype group, that he also thinks it's a genotype group.

So.. the reason why I'm disagreeing with you that Myr's discussion of a phenotype group shows that it is a genetic group is because I don't agree that it does show that, not because I'm supporting some rival contention. We now appear to agree.

In the first place, that would hardly imply that he thinks it isn't a genotype group; it simply gives no information on that point. And in the second place, it doesn't change the fact that "it's a phenotype group" isn't the only thing Mayr said on the subject. He said other things that imply he thinks it's also a genotype group.

Sure, he discusses race as a phenotype categorisation and then discusses whether they may be genetically related.

That's a long way from the idea that race is a coherant genetic group.

The point is, you appeared to jump from the premise that members of a phenotypical group might not be genetically similar to the conclusion that Mayr thinks members of a race might not be genetically similar.

Not my intention.

A race isn't just any old phenotypical grouping; it's a phenotypical grouping with the additional properties of differing taxonomically from other populations...

So are many phenotypical groupings. Alcohol resistance, for example.

Not really on-topic in this forum. But you and the discussion are evidently not to be moved. So I'll quote what I wrote on FRDB the last time I had this debate.

One commonly used measure of genetic distance is called "Fixation Index" or "F_ST". It's a statistical formula that maps the frequencies of a collection of particular genes in people from two populations into an overall measurement of how different the two gene pools are. Dr. Cavalli-Sforza's team computed fixation indices pairwise for forty-two populations, based on published data about 120 genes. They used a computer to analyze the raw genetic distances and identify the best-fitting tree structure. And one of the subtrees in the resulting tree contained all their European sampled populations (including Lapps, Greeks, Basques, etc.), as well as samples from Iran, the Middle East, North Africa, and two samples from India. The genetic distances were 0.05 or less; the minimum genetic distance to other nodes in the tree was 0.11. In short, the computer recognized what is almost the exact category called "Caucasoid" in traditional pre-PC physical anthropology. How did this happen, if there's no such thing as a biological Caucasian? Coincidence?

Quite possibly, yes. If the 150 markers being used are the same ones that drive the phenotypical characteristics that drove the comparison in the first place, then all that's being measured is the same phenotype grouping that was initially selected.

Similarly, if you look into the pariwise comparisons, what you're seeing are between groups measures and intragroups measures. While it's tempting to simply line them up and compare the relative strength, that's not in itself a demosntration of genetic coherence.

Social constructs exist only in the brains of human beings. Does the Fixation Index formula mathematically read their minds?

It could easily be, yes. For example, if you create an entirely arbitrary phenotype group, then you're going to find some genetic markers that they have in common, and which other groups do not have in common. In that sense, the formula is reading your mind, because all it's doing is confirming that within the group you've a priori chosen as signfiicant, there are features you can use to carve out some genetic similarities, that establish the group you've chosen as significant. All it's doing in that case is reinforcing your intiial assumption.

Anyone claiming "Caucasian" is a social construct resulting from drawing arbitrary lines across a featureless terrain of human genetic variation has an awful lot of explaining to do.

Yes, such as 'why are you made of straw?', and 'how did you come to repalce the people who actually disagree with me'.

If you say so. The points I'm making are from the viewpoint of the perils of using clusters of results in the absence of a actual definition. If you grab any old data, and run it through a multivariate analysis, you'll get groups in the results, as long as you have a large enough data set and enough potential dimensions. The mathematical error is to assume that because you can draw a line around a cluster of results, the cluster must somehow be a meaningful group. Hence the astrology comparison. People can be sorted into groups by star signs, but that doesn't in itself make start signs 'real' or meaningful in any way. Similarly, the fact that you can identify a group of people by common genetic markers does not in itself make that grouping useful or significant.

Hey, I didn't claim grouping people into races is useful. It would be nice if we all cared no more about one another's race than we do about one another's ear wax type.

But as to meaningfulness and significance: the difference between grouping stars by finding clusters in their two-dimensional positions on the celestial sphere and grouping people by finding clusters in their hundred-dimensional positions on a hundred phenotypical and/or genotypical axes is that the former has no predictive power and the latter does.

Ok, so you reckon race has predictive power? In the case of individuals? Can you give an example?

Whether a star is two-dimensionally in Pisces or in Ursa Minor tells us nothing about its position in the third dimension: how far away it is. If instead we take a chart of stars' parallaxes and right ascensions and look for clusters, we'll find a completely different set of clusters and define groups with no correlation to traditional constellations; and we'll find those clusters have no power to predict their members' declinations.

And similarly, testing genes in 150 dimensions* does not tell us much about the variations on the other few million.

But people are not stars. Except for a few special clusters like the Pleiades, the clustering in the sky is random. Not so, the clustering in multivariate analyses of phenotypical and genotypical features. Positions along those dimensions cluster the specific way they do because of mankind's history of breaking up into isolated populations. If you repeat your multivariate analysis in a different space, with a different hundred axes measuring a different hundred genes and phenotypical features, you'll get pretty much the same clusters, because there's only one history of who was making babies with whom, and that history created both clustering patterns.

Not following this, I'm afraid. Stars aren't random, and also only have one history. Are you saying that it doesn't matter which genes you track, you'll get the same results? Because that's not a claim I've seen in your sources...

Ok, so when you say 'races biologically exist', what you mean is that:
1) People have genes
2) These genes occur in correlational clusters
3) People with similar patterns of clustering can be labelled as belonging to 'races'
4) These races may not bear any relationship whatsoever to races as the term is commonly understood
5) These races may not have any common traits beyond those clusters

That's not a reasonable interpretation of what I wrote. You cannot plausibly believe that's what I mean.

It's not supposed to be. It's my impression of what the sources you had presented up to that point were demonstrating. Your claims are well in excess of this.

I assume your point is that if I don't recognize "Black" as a race it means I'm using the word "race" in some novel technical sense that would be unrecognizable to the man on the street, and therefore what I'm saying has no implications for the reality of races as commonly understood. Is that what you're getting at?

Sort of. You've used race in two different ways already, to refer to large continental groupings that don't reflect how people in the street use the term (too broad), and in very specific historical geographic sub-sections that don't reflect how people use the term (too narrow). The point I'm making is that it isn't enough to show that there is some sort of genetic group out there, but rather you need one that would make racial distinctions valid at least in theory, or else your banner headline (races are real) is at best highly misleading. That is a point you've sought to address in your most recent post - by claiming that the races being found are the same as those earlier proposed.

What happened is his data showed "Caucasoid", "Negroid" and "Mongoloid" correspond to natural features of the human gene pool. That looks to me like a relationship to races as the term is commonly understood. If that doesn't look to you like a relationship to races as the term is commonly understood, why doesn't it look that way to you?

Because for a 'race' to be a useful and valid signifier, it needs quite a few characteristics. It needs to be identifiable, which we have. It needs to have features intrinsic to the group, and features extrinsic to the group, such that membership of the group is a highly reliable predictor of the presence and absence of various traits outside of those used to identify the group in the first place, and so on.

Because some of the men on the street are so ignorant they think an Australian Aborigine is a "Negro"? That is not a good reason.

Depends on what you're using it for. It is if you're using self-identifcation as your measurement criteria, or if you're advocating public policy.

4) These races are pretty much the conventional races, as the term was commonly understood, by educated people, before ideological race-denialism spread disinformation about the topic;

Well hang on there. You've just defined race through 1)-3) as being genetic clustering with no reference to size other than 'suitably large'. So how big is a 'race', and why is it that size? Tradition? Or is there more to it?

and 5) These races invariably have millions of common traits beyond the genes that were used to identify the clusters.

Cite please.

You mean the Tasmanian Tiger? It didn't look much like a tiger at all except for being striped, so I take it you're comparing it to the wolf. That's a superficial resemblance.

Eh.. Depends on what you choose to measure, which is kinda the point I was making. I think in the absence of an actual defintion, the best we can do is agree to disagree.

Now you may want to suggest that there exist invisible racial distinctions that don't correspond to the racial groups we usually use. That it might be possible to draw a circle around various hereditary groups and identify genes they have in common, even though they don't look particularly similar. But why would this matter?

Why would I want to suggest such a thing, when I could instead suggest that it is possible to draw a circle around various hereditary groups, not by cherry-picking a few genes they have in common but by selecting hundreds of SNPs at random, and observe that they're visible, they do look particularly similar, and they do correspond to racial groups anthropologists usually used before that sort of thing became unfashionable?

Cite please.

Cited above.

Where? All the references you've given thus far talk about using specific sets of genetic markers.

 

[fromderinside]

Where? All the references you've given thus far talk about using specific sets of genetic markers.

Is the the party to whom I am speaking? Great. Why not test Bomb#20's postulations with a specific example of visible traits of Barack Obama and compare them with the his genetic makeup? Is Barack a member of a particular race? Isn't this where the proof lies? Shouldn't one be able to characterize a person as a member of a race by just looking at their apparent physical traits and be confident that her genes validate that conclusion?

 

[Bomb#20]

Is the the party to whom I am speaking? Great. Why not test Bomb#20's postulations with a specific example of visible traits of Barack Obama and compare them with the his genetic makeup? Is Barack a member of a particular race? Isn't this where the proof lies? Shouldn't one be able to characterize a person as a member of a race by just looking at their apparent physical traits and be confident that her genes validate that conclusion?

Barack Obama had himself sequenced and you have access to his genome?

 

[fromderinside]

Is the the party to whom I am speaking? Great. Why not test Bomb#20's postulations with a specific example of visible traits of Barack Obama and compare them with the his genetic makeup? Is Barack a member of a particular race? Isn't this where the proof lies? Shouldn't one be able to characterize a person as a member of a race by just looking at their apparent physical traits and be confident that her genes validate that conclusion?

Barack Obama had himself sequenced and you have access to his genome?

No. I have access to the phenotype of his genetic progenitors which I combine with a bit of basic human reproductive genetics I have in store.

 

[Bomb#20]

Barack Obama had himself sequenced and you have access to his genome?

No. I have access to the phenotype of his genetic progenitors which I combine with a bit of basic human reproductive genetics I have in store.

So if I judge that based on his apparent physical traits, Obama looks like a guy who's heterozygous for the Fy-b allele, you'll be confident that his genes validate that conclusion based on basic human reproductive genetics?

 

[Togo]

No. I have access to the phenotype of his genetic progenitors which I combine with a bit of basic human reproductive genetics I have in store.

So if I judge that based on his apparent physical traits, Obama looks like a guy who's heterozygous for the Fy-b allele, you'll be confident that his genes validate that conclusion based on basic human reproductive genetics?

No, you judge what race he is, which is apparently straightforward and non-controversial unless you're dumb enough to mistake Australians aboriginals for Africans, and work out his traits based on that.

 

[Bomb#20]

So if I judge that based on his apparent physical traits, Obama looks like a guy who's heterozygous for the Fy-b allele, you'll be confident that his genes validate that conclusion based on basic human reproductive genetics?

No, you judge what race he is, which is apparently straightforward and non-controversial unless you're dumb enough to mistake Australians aboriginals for Africans, and work out his traits based on that.

Yeah, I got that. fdi was being sarcastic without being substantive, so I gave him suitably sarcastic answers. If that last one was too obscure, well excuuuuuuse me. Maybe this one will be clearer:

Hey, look everyone! I've just demonstrated the non-existence of genotypical species!

 

[fromderinside]

No, you judge what race he is, which is apparently straightforward and non-controversial unless you're dumb enough to mistake Australians aboriginals for Africans, and work out his traits based on that.

Yeah, I got that. fdi was being sarcastic without being substantive, so I gave him suitably sarcastic answers. If that last one was too obscure, well excuuuuuuse me. Maybe this one will be clearer:

Hey, look everyone! I've just demonstrated the non-existence of genotypical species!

Well gee Bomb#20, I thought you were just being a discussant, not the authority. So let me put in terms which you are more familiar:

But, but, but, daddy. My teacher told me that tigers and lions don't interbreed 'cause they are two different species ......

Wrong child.

Let me refer you to the following:
"Speciation" http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/S/Speciation.html

Enjoy the ride.

 

[Bomb#20]

...
Hey, look everyone! I've just demonstrated the non-existence of genotypical species!

Well gee Bomb#20, I thought you were just being a discussant, not the authority. So let me put in terms which you are more familiar:

But, but, but, daddy. My teacher told me that tigers and lions don't interbreed 'cause they are two different species ......

Wrong child.

Let me refer you to the following:
"Speciation" http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/S/Speciation.html

Enjoy the ride.

Well, thanks for that -- but much though I do enjoy any page that talks about my favorite salamanders (I have E. e. xanthoptica in my yard), I'm not seeing anything in your post that looks like it's intended to be a point.

If you weren't following mine, it was that since the existence of Patrick, who is a lion/tiger cross, evidently isn't a problem for the existence of a genotypical lion species and a genotypical tiger species, why on earth would anyone imagine that Barack Obama, who is a Negroid/Caucasoid cross, would pose a problem for the existence of a genotypical Negroid race and a genotypical Caucasoid race? What exactly is it that you think I postulated, that you believe you can test with the specific example of visible traits of Barack Obama by comparing them with his genetic makeup?

 

[fromderinside]

Well gee Bomb#20, I thought you were just being a discussant, not the authority. So let me put in terms which you are more familiar:

But, but, but, daddy. My teacher told me that tigers and lions don't interbreed 'cause they are two different species ......

Wrong child.

Let me refer you to the following:
"Speciation" http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/S/Speciation.html

Enjoy the ride.

Well, thanks for that -- but much though I do enjoy any page that talks about my favorite salamanders (I have E. e. xanthoptica in my yard), I'm not seeing anything in your post that looks like it's intended to be a point.

If you weren't following mine, it was that since the existence of Patrick, who is a lion/tiger cross, evidently isn't a problem for the existence of a genotypical lion species and a genotypical tiger species, why on earth would anyone imagine that Barack Obama, who is a Negroid/Caucasoid cross, would pose a problem for the existence of a genotypical Negroid race and a genotypical Caucasoid race? What exactly is it that you think I postulated, that you believe you can test with the specific example of visible traits of Barack Obama by comparing them with his genetic makeup?

You have to have a condition before you can have a problem. My point is you haven't demonstrated a condition. Where is the evidence for races among extant humans? Phenotype doesn't really work. It didn't work for Adler, its not working for you.