"Race doesn't exist," and the myth is drowning blacks

[Derec]

If you have a buoyant body, then all it takes to prevent yourself from drowning is to take in a breath of air. You just float to the top. For some people, taking in a breath of air is not enough. They still sink.

What is the density of a very lean human body?

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Blacks disproportionately live in areas with swimming pools.

True. All 4 City of Atlanta indoor (and thus year round) swimming pools have been built in predominantly black areas.

 

[ApostateAbe]

Which part of the data am I misapplying? For example, if blacks have greater bone density on average, then it is more probable that they greater body density on average--yes or no? If no, then why?

Are there any studies which show bone density to be a factor in learning to swim to a skill level sufficient to prevent drowning?

Which is more important to swimming ability, bone density or muscle mass? Is the difference in bone density shown in the studies you cite a great enough difference to make the average black person significantly less buoyant?

All very good questions! Before I answer your questions, I would like you to answer mine.

 

[Derec]

I suppose the child of one black parent and one white parent should be at least able to dog paddle.

Only if they are conceived doggy-style.

Are there any studies which show lighter skinned black people are more buoyant?

I think the ability to swim at all is cultural like that coworker of mine who was proud for not swimming. Biological differences like average lung capacity or body shape can explain things like performance at the highest levels of the sport though.

 

[Bronzeage]

Are there any studies which show bone density to be a factor in learning to swim to a skill level sufficient to prevent drowning?

Which is more important to swimming ability, bone density or muscle mass? Is the difference in bone density shown in the studies you cite a great enough difference to make the average black person significantly less buoyant?

All very good questions! Before I answer your questions, I would like you to answer mine.

My response to your question is that bone density, whether it is higher or lower than average, is a negligible factor in swimming ability.

The human body's weight is about 15% bone, so denser bones cannot have a great effect on overall density.

 

[ApostateAbe]

All very good questions! Before I answer your questions, I would like you to answer mine.

My response to your question is that bone density, whether it is higher or lower than average, is a negligible factor in swimming ability.

The human body's weight is about 15% bone, so denser bones cannot have a great effect on overall density.

OK, that seems like a good argument. Bone density seems to be most often presented as the primary reason for those who favor genetic variations, and it strikes me as a less plausible primary reason than lung size.

 

[Derec]

All very good questions! Before I answer your questions, I would like you to answer mine.

My response to your question is that bone density, whether it is higher or lower than average, is a negligible factor in swimming ability.

The human body's weight is about 15% bone, so denser bones cannot have a great effect on overall density.

15% seems high enough for competitive swimmers where hundredths of seconds make a difference but should not prevent anybody from being a competent swimmer.

 

[Bronzeage]

My response to your question is that bone density, whether it is higher or lower than average, is a negligible factor in swimming ability.

The human body's weight is about 15% bone, so denser bones cannot have a great effect on overall density.

OK, that seems like a good argument. Bone density seems to be most often presented as the primary reason for those who favor genetic variations, and it strikes me as a less plausible primary reason than lung size.

The point I bring up every time you start one of these threads. The body variations within the human population are insignificant when attempting to draw conclusions about differences in racial characteristics. Racial characteristics among humans mean as much as the spot pattern on Dalmatian dogs.

 

[ApostateAbe]

OK, that seems like a good argument. Bone density seems to be most often presented as the primary reason for those who favor genetic variations, and it strikes me as a less plausible primary reason than lung size.

The point I bring up every time you start one of these threads. The body variations within the human population are insignificant when attempting to draw conclusions about differences in racial characteristics. Racial characteristics among humans mean as much as the spot pattern on Dalmatian dogs.

The general criticism I have to that point is that it seems to be imposing human judgments of "significance" on nature, as though it is a general rule, but nature does not know the difference between significant and insignificant. There are genetic differences among the races for many genotypes and phenotypes, some subjectively significant and some not. A victim of cystic fibrosis may find it significant that the purely-genetic disease is ten times as common among whites than among Asians, but maybe you wouldn't.

 

[Keith&Co.]

For all we know right now, only 2% of the applicants are black in the first place, so the number of graduates compared to the number of sailors overall is a meaningless ratio.

Presumably the non-swimmers would be weeded out well before the formal application process.

Well, no one applies to the SEALS and has the audacity to look surprised when he's asked to swim across the harbor.

But is there any data on blacks being under-represented in the SEALS exactly because they have a hard time with the swimming requirements?

 

[Bronzeage]

The point I bring up every time you start one of these threads. The body variations within the human population are insignificant when attempting to draw conclusions about differences in racial characteristics. Racial characteristics among humans mean as much as the spot pattern on Dalmatian dogs.

The general criticism I have to that point is that it seems to be imposing human judgments of "significance" on nature, as though it is a general rule, but nature does not know the difference between significant and insignificant. There are genetic differences among the races for many genotypes and phenotypes, some subjectively significant and some not. A victim of cystic fibrosis may find it significant that the purely-genetic disease is ten times as common among whites than among Asians, but maybe you wouldn't.

Cystic fibrosis is caused by having two recessive genes. One CF gene makes a person more resistant to Rheumatic Fever. It's a northern European trait, similar to the Sickle Cell gene, which protects a person from malaria and other blood borne pathogens. The lucky person would be the one who has one of each. The diseases associated with these genes are the result of too small a population and not enough diversity in their gene pool. These genetic traits are the result of the environment in which they live, not some sort of fault in their racial type.

 

[ApostateAbe]

The general criticism I have to that point is that it seems to be imposing human judgments of "significance" on nature, as though it is a general rule, but nature does not know the difference between significant and insignificant. There are genetic differences among the races for many genotypes and phenotypes, some subjectively significant and some not. A victim of cystic fibrosis may find it significant that the purely-genetic disease is ten times as common among whites than among Asians, but maybe you wouldn't.

Cystic fibrosis is caused by having two recessive genes. One CF gene makes a person more resistant to Rheumatic Fever. It's a northern European trait, similar to the Sickle Cell gene, which protects a person from malaria and other blood borne pathogens. The lucky person would be the one who has one of each. The diseases associated with these genes are the result of too small a population and not enough diversity in their gene pool. These genetic traits are the result of the environment in which they live, not some sort of fault in their racial type.

I agree, and I extend those patterns to racial differences generally. It is not about which genes are better or worse than others, but it is about genetic differences among populations following from natural selection, mating selection, inbreeding, bottlenecks and genetic drift.

 

[Loren Pechtel]

What is the density of a very lean human body?

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Blacks disproportionately live in areas with swimming pools.

True. All 4 City of Atlanta indoor (and thus year round) swimming pools have been built in predominantly black areas.

I was thinking more of outdoor pools--they are more common in warmer climates. Blacks tend to be in warmer areas because that's where they were brought as slaves.

 

[scombrid]

The opening post fails to demonstrate that the "black phenotype" is significantly less buoyant than white and that this buoyancy difference precludes black people from learning how to swim.

I'm very white. I'm also very lean and muscular, far more so than the average any person. I can exhale and sink right to the bottom of a pool like a rock. I swim just fine.

 

[ApostateAbe]

The opening post fails to demonstrate that the "black phenotype" is significantly less buoyant than white and that this buoyancy difference precludes black people from learning how to swim.

I'm very white. I'm also very lean and muscular, far more so than the average any person. I can exhale and sink right to the bottom of a pool like a rock. I swim just fine.

In the OP, I listed three reasons to expect that the black race (not "black phenotype") is significantly less buoyant than the white race. It is not conclusive, but I think they should be considered more useful than anecdotes!

 

[fromderinside]

The opening post fails to demonstrate that the "black phenotype" is significantly less buoyant than white and that this buoyancy difference precludes black people from learning how to swim.

I'm very white. I'm also very lean and muscular, far more so than the average any person. I can exhale and sink right to the bottom of a pool like a rock. I swim just fine.

In the OP, I listed three reasons to expect that the black race (not "black phenotype") is significantly less buoyant than the white race. It is not conclusive, but I think they should be considered more useful than anecdotes!

Sorry. Its anecdote versus anecdote. You have not even made an argument IMHO.

 

[ApostateAbe]

In the OP, I listed three reasons to expect that the black race (not "black phenotype") is significantly less buoyant than the white race. It is not conclusive, but I think they should be considered more useful than anecdotes!

Sorry. Its anecdote versus anecdote. You have not even made an argument IMHO.

I am not sure we speak the same language!

 

[scombrid]

In the OP, I listed three reasons to expect that the black race (not "black phenotype") is significantly less buoyant than the white race.

You assert a phenotype peculiar to the "black race" that precludes them being able to swim. I called that "black phenotype" for shorthand.

It is not conclusive, but I think they should be considered more useful than anecdotes!

Your assertion that black lung volume is insufficient for swimming does not agree with widespread success in endurance sport that require a high VO2 max.

 

[ApostateAbe]

I found a study that quantified the average body densities of white men and black men. No need to rely on the physiological patterns. The study is titled, "Prediction of Body Density from Skinfolds in Black and White Young Men," published in Human Biology in 1988. The prediction is correct. The study found that young white men have an average body density 1.065 g/ml, and young black men have an average body density of 1.075 g/ml.

If this seems like small difference, remember it is in the context of the baseline of water density being about 1 g/ml. That is the division between sinking while relaxed and floating while relaxed. Pool water is a little less dense due to the chlorine, at 0.993 g/ml. Seawater is a little more dense, at 1.025 g/ml (which makes anyone less likely to sink in the ocean). So, in pools, the average white man has 14% more buoyant force than the average black man [(1.075-0.992720)/(1.065-0.992720)=1.14]. BuoyantForce=(weight of body)*(density of fluid)/(density of body), and the only significant variant is the density of body.

 

[Bronzeage]

I found a study that quantified the average body densities of white men and black men. No need to rely on the physiological patterns. The study is titled, "Prediction of Body Density from Skinfolds in Black and White Young Men," published in Human Biology in 1988. The prediction is correct. The study found that young white men have an average body density 1.065 g/ml, and young black men have an average body density of 1.075 g/ml.

If this seems like small difference, remember it is in the context of the baseline of water density being about 1 g/ml. That is the division between sinking while relaxed and floating while relaxed. Pool water is a little less dense due to the chlorine, at 0.993 g/ml. Seawater is a little more dense, at 1.025 g/ml (which makes anyone less likely to sink in the ocean). So, in pools, the average white man has 14% more buoyant force than the average black man [(1.075-0.992720)/(1.065-0.992720)=1.14]. BuoyantForce=(weight of body)*(density of fluid)/(density of body), and the only significant variant is the density of body.

With this information, it would seem blacks would be better divers than whites, as it takes less effort to sink.

 

[ApostateAbe]

I found a study that quantified the average body densities of white men and black men. No need to rely on the physiological patterns. The study is titled, "Prediction of Body Density from Skinfolds in Black and White Young Men," published in Human Biology in 1988. The prediction is correct. The study found that young white men have an average body density 1.065 g/ml, and young black men have an average body density of 1.075 g/ml.

If this seems like small difference, remember it is in the context of the baseline of water density being about 1 g/ml. That is the division between sinking while relaxed and floating while relaxed. Pool water is a little less dense due to the chlorine, at 0.993 g/ml. Seawater is a little more dense, at 1.025 g/ml (which makes anyone less likely to sink in the ocean). So, in pools, the average white man has 14% more buoyant force than the average black man [(1.075-0.992720)/(1.065-0.992720)=1.14]. BuoyantForce=(weight of body)*(density of fluid)/(density of body), and the only significant variant is the density of body.

With this information, it would seem blacks would be better divers than whites, as it takes less effort to sink.

Yes, good point. Black slaves were actually used for pearl diving.