We know that some species are more sexually dimorphic than others. Species with big differences are polygamous and are called "tournament" species (due to the intense male-male competition) while those with small sex differences are monogamous and are called "pair-bonding" species. (Small) differences might exist across human races as well.
One indication of the degree of dimorphism is the gender difference in life expectancy. According to the NCHS, current life expectancy is 80.6 years for (non-Hispanic) white females and 75.8 years for white males. So among whites, women live 4.8 years or 6.3 percent longer. Expectancies among (non-Hispanic) blacks are 76.5 for women and 69.6 for men. So black women live 6.9 years or 9.9 percent longer. I take this as evidence that blacks are more sexually dimorphic than whites. (Keep in mind that racial differences are reduced since American blacks have roughly 20 percent European ancestry.)
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nah dude. forensics guys have more difficulty distinguishing the sexes of black skellies than white or asian ones.
I take this as evidence that blacks are more sexually dimorphic than whites. (Keep in mind that racial differences are reduced since American blacks have roughly 20 percent European ancestry.)
That's a very flawed theory. Based on it, we would predict that blacks in Africa would show an even greater discrepancy between male and female life expectancy. But in South Africa the numbers are 48.8 years for men and 49.7 for women. In Namibia, 52.5 years for men and 53.1 for women. And so on for the other black African countries.
The underlying assumption is mistaken, as life expectancy is a poor indicator of sexual dimorphism. But if we assume that life expectancy is a good indicator of sexual dimorphism, we'd have to conclude that blacks are less sexually dimorphic than others races. (Including Asians - check out the male/female life expectancy in countries like Japan)
IIRC size dimorphism actually increases with distance from the equator, while polygyny decreases. Sociobiologists have attempted to link the two in humans a number of times over the last several decades, and the results keep turning up nil.
Why look at such a indirect corelate instead of actual size>
White men and women are just barely taller then black men and women the gap is almost exactly the same
http://www.uscg.mil/hq/cg5/cg5212/docs/nchs-ad347.pdf
Black men are about 2 pounds heavier on average then white, while black women are 18 pounds heavier then white women. So here the predicted relationship is reversed. This very likely due to obesity, though it is certainly plausible that black women are more robustly built even sans excess adiposity. That my anecdotal observation but its impossible to parse from the data given the ubiquity of obesity.
Inductivist --
The difference you are seeing is probably mainly due to crome related death of youths. Many black men do not live out their full life expectancy.
In Russia, due to heavy alcoholism, many men do not live out their full live expectancy. There is an even larger gap among Russian men.
Your thesis is absolutely correct. But the analysis could be much simpler. Black men have on average 20% higher serum testosterone than whites. Black women have 20% higher serum estrogen the whites, studies have shown.
Black men have on average 20% higher serum testosterone than whites. Black women have 20% higher serum estrogen the whites, studies have shown.
Bullshit. This is one of the more fantastic and indestructible myths of HBD-land.
Here is a link to an actual scientific study. Since you seem to be the sort of idiot who cannot read, I'll tell you the conclusion: there is no difference in testosterone levels between the races.
The study finds no difference between black and white men, to be precise.
And you can see from this thread how march-step HBDers are.
Salivary T levels markedly lower in African than "Western" males.
"there is no difference in testosterone levels between the races."
T levels aren't the whole story. there are differences in androgen receptor sensitivity -- blacks have more sensitive receptors. this would explain their greater muscular tone (lower marbling) than white men. btw, greater muscular tone does not necessarily mean greater strength. i believe the strongest men are nordics and central asians.
T levels aren't the whole story. there are differences in androgen receptor sensitivity -- blacks have more sensitive receptors. this would explain their greater muscular tone (lower marbling) than white men
Can you cite any evidence that (a) black men have "more sensitive (androgen) receptors" than other men, and (b) that black men have "greater muscle tone" (by which you seem to mean a lower body fat percentage) than other men?
Studies have found that while black women have a higher proportion of body fat than white women, white and black men are identical in this respect.
I'd suggest that you look arond you at black men and trust the evidence of your eyes, but let's be realistic here - your argument is based on selection bias.
Your knowledge of black men is based largely on the black athletes you see on TV. If you're a college graduate, and I assume you are, then you probably saw black men at college - virtually all of whom were there on athletic scholarships. Based on this sample you've come to the conclusion that black men are superior physical specimens. If your sample was instead military special forces, for instance, you'd have come to a different concluson.
"Bullshit. This is one of the more fantastic and indestructible myths of HBD-land.
Here is a link to an actual scientific study. Since you seem to be the sort of idiot who cannot read, I'll tell you the conclusion: there is no difference in testosterone levels between the races."
Easy there, tiger. Don't be a hater. Don't go soft on HBD just because it doesn't give you the results you like in all instances.
I know, I know, those 100 meter dash winners have all been white for the last 30 years.
Its been 100 years since Jack Johnson ended the hunt for the great white hope. Can we get over it?
That study you cite:
http://jcem.endojournals.org/content/92/7/2519.full
Is total nonsense. They correct for body fat, which is basically throwing out the baby with the bathwater. Body fat itself is a function of T.
Sailer notes that it is likely young blacks lower body fat.
http://isteve.blogspot.com/2006/04/less-body-fat-and-denser-bones.html
Bone density is heavily correlated with T and this is what you see:
http://depts.washington.edu/bonebio/bonAbout/race.html
C'mon, people man up. If HBD doesn't go your way in all instances, don't go freaking out about it!
Ugh. "Sprinting" again. Can an HBD conversation exist without a reference to black's sprinting ability? I agree with the poster who said black test levels are not higher. HBDers have an intense attachment to a mythological view of black physical ability. I think it might be a gay thing tbh.
I know, I know, those 100 meter dash winners have all been white for the last 30 years.
You are mixing all sorts of different things into a stew. Sprinting ability has to do with certain physiological traits, of course, but body fat percentage is not one of them. The proportion of fast-twitch to slow-twitch muscle fiber is more meaningful in this regard.
By the same token, I'm already aware that blacks tend to have denser bones then non-blacks. But you're changing the subject again - your initial claim was that blacks (men and women) have "greater muscular tone (lower marbling)" then non-blacks. And that claim remains false.
Bone density is heavily correlated with T and this is what you see
Can you cite any studies to the effect that bone density is heavily correlated with testosterone? You're wrong yet again - it is estrogen which is the hormone heavily correlated with bone density. And lo and behold! studies HAVE found that black men have higher levels of estrogen than white men.
Sailer notes that it is likely young blacks lower body fat.
"Notes" and "is likely" is just another way of saying "speculates". Sailer does not offer a single shred of hard evidence to support his supposition that black males have lower body fat than white males. It's just the same silly HBD-sphere myth repeated over and over.
Body fat by race and sex.
Results: White and black men have the same proportion of body fat. Black women have more body fat than white women, a result not consistent with their having higher testosterone.
Americans in general - white and black, male and female - are a pretty fat bunch who need to eat less and/or exercise more.
That is what the data says. My own comment: the myth of the black male as a lean mean killing machine with gallons of testostrone pumping through his veins is one which seems to be very emotionally appealing to a lot of white guys. I can't quite figure out why, but I'd speculate that believing this gives these same white guys an excuse for constantly backing down when confronted by blacks.
"It's not that I'm a coward, it's just that it would be as irrational for me to fight a black guy as it would be for me to fight a grizzly bear".
But that's not a belief which has any scientific basis.
Studies have shown somewhat higher T in black men. Why is everyone getting their panties in a bunch over that? People are acting like that will cause their psyche to fold like a cheap suit. Guess what, my T level is not the be-all of my self worth.
Bernstein L, Ross RK, Judd H, et al (1986). Serum testosterone levels in young black and white men. J Natl Cancer Inst 76:45—48, 1986
Ross, R.K., Coetzee, G. A., Reichardt, J., Skinner, E, and Henderson, B.E. (1995). Does the Racial-Ethnic Variation in Prostate Cancer Risk Have a Hormonal Basis? Cancer, Volume 75, Issue S7 (p 1778-1782)
Ross R.K., Henderson B.E. (1994). Do diet and androgens alter prostate cancer risk via a common etiologic pathway? / Natl Cancer lnst 1994; 86:252-4.
Now, hallelujah! A new study 'corrects' for a bunch of factors to get whites and blacks to the same T, all other things being equal, even though the raw data, which corresponds to the people you actually meet on the street, shows a difference. Well you can account for a lot of difference between men and women's T by noting that men are taller, heavier, leaner and have more muscle mass. Obviously it is retarded to correct for things that are correlated to T, such as body fat.
Studies have shown somewhat higher T in black men. Why is everyone getting their panties in a bunch over that?
? "panties in a bunch"? You don't come across as the sharpest knife in the drawer.
Studies, such as the two already mentioned, do NOT show higher T in black men. Your reaction to facts which you don't like is to get silly and irrational.
Guess what, my T level is not the be-all of my self worth.
It would seem that the same holds true for your IQ level.
you can account for a lot of difference between men and women's T by noting that men are taller, heavier, leaner and have more muscle mass
It seems to have somehow escaped your attention, Einstein, that black men are not taller, heavier, and leaner than white men. But your contempt for mere reality is nothing new here.
A new study 'corrects' for a bunch of factors to get whites and blacks to the same
You're a moron. Black men and white men have the same body fat percentage, as was already documented in an earlier link. Your theory that "correcting for body fat" introduced errors into the T study merely shows that you lack the intelligence to understand these topics, let alone to discuss them.
In theory HBD offers a useful corrective to mainstream liberalism's refusal to discuss inate human differences. In practice a lot of people you see commenting on HBD blogs are ignorant bigots seeking to have their prejudices confirmed.
The theory that prostate cancer is linked to elevated testosterone levels is already under attack.
Link.
Bernstein L, Ross RK, Judd H, et al (1986). Serum testosterone levels in young black and white men. J Natl Cancer Inst 76:45—48, 1986
Now, hallelujah! A new study 'corrects' for a bunch of factors to get whites and blacks to the same T, all other things being equal, even though the raw data, which corresponds to the people you actually meet on the street, shows a difference.
If you took the trouble to look up and read the studies you mention, which you plainly never do, you'd see that they also "correct for a bunch of factors", as you so scientifically put it.
For instance, here is the abstract of the study by Bernstein, Ross et al, which employed "adjustment by analysis of covariance for time of sampling, age, weight, alcohol use, cigarette smoking, and use of prescription drugs".
So there is nothing new or startling about a study correcting for a "bunch of factors". This cannot explain why different studies produce different results.
As for "the people you actually meet on the street", I don't know what your subjective experience is. But speaking as a six foot tall white guy with 12% body fat, I've never noticed that black guys in my own neck of the woods are unusually tall and lean. And in fact the data already cited in this thread shows that the typical black man is both shorter and fatter then I am. (The same is true for the typical white man, of course)
I notice that the Ross study was of "white and black college students in Los Angeles, CA". That right there suggests a source of error - here in America, for some amazingly stupid reason, white college students get into college by being smart, while black college students get into college by being athletes. In other words the study wound up selecting, by accident rather than by design, white nerds and black jocks.
The Rohrmann study which found no difference in T levels was of a more realistic cross section of the population.
"Can you cite any evidence that (a) black men have "more sensitive (androgen) receptors" than other men"
Here ya go:
"The androgen receptor genotype was determined in the white blood cell DNA of 45 African-American, 39 non-Hispanic white, and 39 Asian (Chinese, Japanese) normal subjects and 68 patients with prostate cancer (57 whites), all of whom were residents of Los Angeles County. For each subject, we measured the number of repeats in the polymorphic CAG and GGC microsatellites of exon 1 of the androgen receptor gene. In normal subjects, the distributions of CAG and GGC microsatellites differed significantly among the races (two-sided P = 0.046 and <0.0005, respectively). The prevalence of short CAG alleles (<22 repeats) was highest (75%) in African-American males with the highest risk for prostate cancer, intermediate (62%) in intermediate-risk non-Hispanic whites, and lowest (49%) in Asians at very low risk for prostate cancer."
http://cancerres.aacrjournals.org/content/55/9/1937.abstract?ijkey=bd15c629504d26ddeb8eb07e0a9cbc0a522df8ee&keytype2=tf_ipsecsha
Anybody who walks outside and observes black and white teenagers playing pickup ball or just milling about shirtless can tell you that the black teens are much more toned than the white kids. most conspicuously, blacks have much more developed deltoids than whites. no maybe the fat to lean muscle ratio changes into adulthood as blacks take on more bad eating habits, but the basal level of muscularity and tone is greater in blacks than in whites. and this has nothing to do with selection bias.
Anybody who walks outside and observes black and white teenagers playing pickup ball or just milling about shirtless can tell you that the black teens are much more toned than the white kids.
What planet do you live on? I served in the army for several years. I've seen plenty of black and white guys shirtless, and pantless too. And they do not "seem to be much more toned than the white guys".
Seriously, where specifically have you ever seen black guys sans shirts?
the basal level of muscularity and tone is greater in blacks than in whites. and this has nothing to do with selection bias.
Unless you tell me what basis you have for these assertions, we cannot rule out selection bias in your forming them.
At present it sounds like you spend too much time watching TV and mistaking it for reality.
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