Race Realism Human biodiversity

Race Realism

This post is going to be a response to a video by Zaunstar entitled “How Much Sunshine can Race Realism Take?” (70). In his video Zaunstar spends a good deal of time on topics of no substance. I am going to ignore all of that in favor of addressing what substance there is in his video. This video is going to be rather lengthy. That is because, despite what some might imagine, race realism is a topic that involves a lot of empirical evidence and going through it all takes time. 

Zaunstar asks what a race realist's ideal America would look like and how race realists think we should achieve this ideal state. This suggests that Zaunstar has a misunderstanding about the meaning of race realism. Race realism is the view that races are real biological categories and that there are important genetic differences between them. That's it. Race realists do not believe that all the differences between the races are genetic in origin. We aren't genetic determinists. And race realism does not entail any particular political views. I've known race realists who are libertarians, fascists, communists, social democrats, and everything in-between. All it means to be a race realist is that you recognize that there are important genetic differences between the races. 

Zaunstar also claimed that there was no good evidence showing that some races are more intelligent than others. In the comment section of his video he further elaborated that race realists rely on non-peer reviewed “garbage science” to substantiate the claim that the races differ in mean IQ. This is incorrect. In fact, there is a wealth of evidence demonstrating that some races and more intelligent than others, that this difference is important, and that it is probably partially genetic in origin. 

The Size and Significance of Race Differences in Intelligence

To begin with, a 2001 meta-analysis published in Personnel Psychology of more than 100 studies which included more than 6 million participants found that blacks score, on average, about 16-17 points lower than whites on IQ tests (1). The same meta-analysis also showed that Hispanics have a higher mean IQ mean than blacks but a lower mean IQ than whites. Other studies have shown that East Asians and certain groups of Jews have higher mean IQ's than whites do (2).

Most researchers who study intelligence realize that IQ tests don't perfectly measure intelligence, but they also realize that a measure doesn't have to be perfect to be useful. IQ tests measure traits like mathematical ability and general knowledge which are commonly thought to at least make up part of intelligence. And how well you do on an IQ test predicts how well you will do in school and how much money you will end up making (3) (4). IQ is also stimulated by going to school (6). Additionally, how well a person does on an IQ test has been shown to correlate with how intelligent they think they are and how intelligent people that know them think they are (72). And people in professions that obviously require a good deal of intelligence, such as doctors, lawyers, and professors, score much higher on IQ tests than people in less cognitively demanding jobs do (7). So there are some pretty good reasons to think that IQ tests measure intelligence.

Some people worry that IQ tests aren't reliable. This means that how well people do on IQ tests is largely dependent on the circumstances under which they happen to be taking the test. For instance, people might think that what a person happens to eat for breakfast, or how they happen to feel that day, or even what the weather out side is like, might have an important impact on how well a person does on an IQ test. The feared result of this would be that IQ tests would measure unique features of the test taker at the moment he was taking the test and not anything stable about a person. This fear is easy to dispel. Studies on IQ test reliability show that how well a person does on an IQ test one day predicts with an extreme degree of accuracy how well they will do on an IQ test taken on another day (8). 

But even if IQ tests didn't reliably measure intelligence, they would still measure something important. And because of this, racial differences in IQ would still matter. For instance, Charles Murray and Richard Herrnstien's analysis of the National Longitudinal Survey of Youth demonstrated that many of the social inequalities between the races disappear or significantly lessen when you control for IQ (9). They found that blacks were actually more likely than whites to graduate from high-school and college once you controlled for IQ. They also found that controlling for IQ causes the wage gap between whites and blacks to shrink from blacks making 77% of what whites make to blacks making 98% of what whites make. Additionally, it was found that controlling for IQ decreased the black/white gap in incarceration rates by about 75%. 

Race, IQ, and Genes

We've seen that IQ tests measure something important and that is related to intelligence. Ad we've seen that the races differ in mean IQ and that this accounts for a lot of the racial inequality found in contemporary America. But this doesn't tell us why the races differ in intelligence. Most race realists take what is called a hereditarian position on this question. A hereditarian believes that a substantial part of racial differences in intelligence are due to genes. This does not mean that all of the differences are due to genes. And it does not mean that they are inevitable. Again, race realists are not genetic determinists. Here I'm going to review some of the evidence in favor of hereditarianism. This review isn't meant to be comprehensive. This is a massive subject. I'll further limit my review to data concerning the IQ difference between blacks and whites because there is more data about this gap than there is for any other racial IQ gap. 

The first explanation most people think of when they hear that the blacks score lower than whites on intelligence tests is that black intelligence is depressed by poverty. While this is an plausible first guess, most researchers recognize that SES actually has very little to do with the B/W IQ gap. As explained in a report on intelligence issued by the American Psychological Association, the fact is that the majority of the B/W IQ gap remains after controlling for socio-economic status (10). In fact, poor white children score better on standardized tests than rich black children do (11). And the IQ gap between rich black and white children is greater than the IQ gap between poor black and white children (12).

Another common environmental explanation of the B/W IQ gap is that blacks score worse than whites on intelligence tests because of discrimination. This theory is often formulated in a vague way that doesn't easily lend itself to testing. However, it is generally agreed upon that American society was more racist in the past than it is today. This fact leads us to a testable prediction: if racism has decreased in America over the least century, and racism causes the B/W IQ gap, then the B/W IQ gap should have decreased over the last century as well. Researchers who have reviewed decades worth of data have shown that this is not the case. The B/W IQ gap has been basically the same since we first measured it in 1918 (13). It seems hard to imagine that a gap caused by racism wouldn't be reduced by the massive strides towards racial equality that the United States has seen over the last 100 years.

Another popular environmental explanation for the B/W IQ gap is that IQ tests are biased in such a way that they favor whites over blacks even though blacks are just as intelligent as whites. A large number of studies have shown that IQ tests are equally predictive of life outcomes for both blacks and whites (14). And the questions that whites find the hardest on an IQ test are the same as the questions that blacks find the hardest (14). This suggests that IQ tests measure intelligence equally well in both populations and that the tests are not biased.

Another popular environmental explanations for the B/W IQ gap is that black families raise their children in such a way that leads to them being less intelligent. For instance, it is claimed that black families talk to their infants less, read fewer books to them, keep less educational material around the house, and don't encourage their children to value education to the degree that white parents do. The Minnesota Transracial Adoption study casts doubt on this kind of explanation. This study showed that black children adopted into the homes of middle class white families end up with the same IQs as black children raised in black families (15). It therefore seems highly unlikely that anything involving family practices can account for the B/W IQ gap.

Yet another environmental explanation for the B/W IQ gap states that it is accounted for by a large number of environmental factors each of which make only a small contribution to the gap. Specific factors normally mentioned in such an argument include stress, exposure to toxins, and mal nutrition. Two facts that I have already noted show that these explanations are unlikely. First, all of these variables are more common among the poor than among the wealthy. If they account for the B/W IQ gap then we should expect that controlling for income would control for most of the B/W IQ gap. But, as we have seen, it does not. In fact, as I have already noted, the B/W IQ gap is largest among blacks and whites from rich families. This fact is pretty hard to reconcile with the view that the B/W IQ gap is caused by something like malnutrition. Secondly, for virtually all of these variables blacks and whites were more unequal in the past than they are now. This should lead us to expect that the B/W IQ gap has decreased over time. But, as we have seen, it has not. 

As has been shown, the evidence suggests that racism, poverty, differences in family life, nutrition, exposure to toxins, test bias, ect, cannot explain most of the B/W IQ gap. This alone makes a genetic explanation of the gap probable. But there is also evidence specifically in favor of a largely genetic explanation.

First, there the implausibility of absolute egalitarianism (the view that genes play no role in the B/W IQ gap). We know that the races evolved to posses differences in height, body size, body shape, skeletal features, blood types, organ sizes, ect. In fact, just about every aspect of our bodies seems to have evolved to differ at least a little between the races. The idea that intelligence just so happens to be an exception to these selective pressures seems highly implausible. On a molecular level, just about every polymorphic gene variant tested differs in frequency between the races (16). And there are thousands of genes involved in producing complex traits like intelligence. The idea that the races just so happen to posses identical frequencies of each of these thousands of variants is extremely improbable.

Second, there is data concerning brain size. Meta analyzes of huge numbers of studies have established the smarter a person is the larger their brain will tend to be (17). And there are specific gene variants which are associated with both larger brains and greater intelligence (18). One possible explanation for why people with this gene variant have both larger brains and greater levels of intelligence is that the gene variant makes people smarter by increasing their brain size. Additionally, changes in brain size across time predict changes in intelligence over time (19). Lastly, it is generally true that the larger a brain region is the larger its effect will be. And intelligence is produced by a large number of different brain regions (20). So it is entirely predictable that larger brains will tend to cause people to be more intelligent. This is relevant to racial differences in intelligence because there is a vast literature showing that white people have larger brains than black people do (21). This race difference in brain size has been found around the world and has been found to be present as early as infancy (22). And controlling for brain size has been estimated to decrease the B/W IQ gap by about 6 points (72). So it seems likely that white people have evolved to posses larger brains than blacks and that this explains part of the B/W IQ gap. 

Thirdly, there is data on the IQ of mixed race children. If the B/W IQ gap is mostly due to genetics then the children of black and white inter racial couples should have mean IQs roughly in-between the mean IQs of blacks and whites. After all, half of their genes that affect intelligence came from a black person and half from a white person. There are a variety of studies that confirm this (5). And the trans-racial adoption data previously referred to shows that mixed race children have intermediate IQ's even when they are raised in the same environment as the blacks and whites they are being compared to.

A fourth source of evidence comes from studies on white admixture and IQ. Measuring a black persons level of white admixture is a way of genetically measuring the extent to which their ancestors bred with white people. The greater the level of white admixture present in a black persons genome to more their genome resembles that of a white person. The hereditarian position predicts that a black person's degree of white admixture will be positively associated with their intelligence level. There are two sources of evidence which suggest that this prediction is accurate. First, there are studies on skin color (67). The lighter a black person's skin is the more white admixture they probably posses. And studies have found that the lighter a black persons skin is the more intelligent they are likely to be. Secondly, studies which directly measure white admixture at the molecular level have found that the greater the level of white admixture present in a black persons genome the greater their family income and level of educational attainment is likely to be. (69). Of course, neither of these variables are equivalent to intelligence. But, as we have already seen, both are highly correlated with intelligence. 

A fifth piece of evidence comes from sub-test heritability. IQ scores are averages based on how someone did on a variety of mental tests. And, using twin studies, it has been shown that some of these tests are more heritable than others. It has also been found that the B/W IQ gap is larger on some tests than it is on others. It turns out that the B/W IQ gap is larger for the most heritable mental tests and smallest for the least heritable ones (23). This is obviously predicted by a theory which states that most of the gap is due to genetics. But it is extremely difficult to explain with any theory that does not.

Finally, there are a several studies which have compared the frequencies with which the races posses specific genes that have been associated with intelligence. They have found that white populations posses genes that predict high intelligence with a greater frequency than black populations do (24) (25).

Zaunstar complains that there is no consensus among researchers about race and intelligence. He is correct to say that there is no consensus. But how many people believe something doesn't determine if it is true or false. The evidence is all open for the public to see. We can evaluate it for ourselves. And such an evaluation heavily favors a hereditarian viewpoint. 

Race Differences in Crime

Zaunstar also commented on race differences in crime. He argues that race is a poor predictor of crime, especially relative to economic factors, and variables concerning family upbringing. Moreover, he argues that any association that does exist between race and crime must be explained by factors such as institutional racism and not by a person’s race having a direct effect on how likely they are to be a criminal. Like his comments about race and intelligence, zaunstar is wrong about race and crime. 

According to the the FBI's uniform crime report, black people accounted for about 28% of arrests in 2012 (26). And according to the Census Bureau, that year blacks made up about 13% of the US population (27). So black people get arrested at more than twice the rate that we would expect if they committed crime at the same rate as non-blacks. Whites, by contrast, accounted for fewer arrests in 2012 than their proportion of the general population would predict. These differences are more pronounced in some areas than others. Among the largest differences can be found in the cases of murder and robbery. In 2012, blacks accounted for 49 % of murder arrests and 55% of robbery arrests. In both cases blacks were arrested more than whites even though blacks are only 13% of the population. Blacks also accounted for 40% of arrests for carrying an illegal weapon, 33% of forcible rape arrests, and 31% of drug related arrests. 

Some people suppose that the high black crime rate is a unique feature of African American culture. In fact, it is not. A paper published in Population and Environment, using data on violent crime rates collected across 72 countries, and over multiple years, found that black nations have much higher rates of violent crime than white nations do (28). And the united states is not the only white country in which blacks are disproportionately represented in arrest rates (29). 

We don't know when the B/W crime gap began, but we do know that it existed as far back as our records go. For instance, census data in the US from as early as 1910 shows more blacks living in jail than whites (30). The exact size of the racial crime gap has varied with time. But its existence has been a constant for at least 100 years. 

The FBI's Uniform crime report shows that blacks are over represented for juvenile arrests just like they are for adult ones (31). This difference in misbehavior is also evident in school. The department of education provided some useful information on this in a 2012 analysis of data on students in kindergarten through high-school from over 72,000 schools (32). It found that blacks made up 18% of the student population, but 35% of students who had been suspended once, 45% of students who had been suspended more than once, and 39% of students who were expelled. In 2014 the Department of education conducted another analysis, this time looking at data from preschool (33). The study found that, even in preschool, blacks were several times more likely than whites to be seriously disciplined. 

How Well Do Race and Poverty Predict Crime?

Zaunstar claims that race isn't very predictive of crime and that socio-economic variables are. To demonstrate this he links to an article which looks at how well various variables predict crime at the individual and community level. Race is not one of those variables. Thus, Zaunstar's claim is unfounded: you can't know that SES is more predictive of crime than race is if you only know the predictive power of SES. In fact, race is a very powerful predictor of crime. For instance, one analysis which looked at government issued data over a several decade period found that the proportion of blacks in a city correlated at (.8) with a cities homicide rate (34). This means that differences in the proportion of blacks present in different cities literally explains the majority of homicide variation between cities. The same analysis showed that race was more predictive of an area's crime rate than its level of poverty or median income. Other analyzes have shown that the racial make up of an area is more predictive of crime than the areas level of unemployment and education (35). Thus, race is actually a very sound predictor of crime. 

Some of the variables mentioned by Zaunstar are legitimate predictors of crime, but poverty is not one of them. A paper published in Social Pathology looked at 45 different studies that assessed whether or not there was a correlation between income inequality, absolute poverty, and violent crime (36). Across these 45 studies 68 total correlations were found between absolute poverty and violent crime. Of them only 25, or 37%, statistically significant and positive. Across these studies there were 59 correlations found between income inequality and violent crime. Of them 27, or 46%, were statically significant and positive. This means that majority of these studies failed to find a statically significant positive correlation between either income inequality or absolute poverty and crime.

Another paper published in “Population and Environment” look at the relationship between wealth and crime at the national level (37). It found that poorer nations did tend to have higher levels of crime. But this was only true for non-black nations. Richer black nations actually had more crime than poorer black nations did. 

On the whole then, both at the national level and at lower levels of aggregation, the evidence does not suggest that how poor an area is is a good predictor of how much crime it will have. This is especially true of black areas. On the other hand, the data does suggest that race is a very powerful predictor of crime. Certainly more so than the socio-economic variables that are normally thought to be associated with criminality. 

Racism and Racial Differences in Crime

As I mentioned previously, Zaunstar claims that any association that exists between race and crime must be explained by confounding variables such as racism. There are two ways in which racism might account for the racial crime gap: racism might cause blacks to be arrested more even though they commit the same amount of crime as whites or racism might cause blacks to commit more crime than whites. Because Zaunstar didn't specify which he meant, I am going to explain why both ideas are not supported by the relevant data. 

Some of the most important data comes from the National Victimization Survey. In this large and annual survey thousands of participants are asked if they have been the victim of any violent crimes in the last year. If they have, they are asked to describe the crime and the perpetrator. In this survey, which has been given annually for decades, people routinely report being victimized by black offenders at rates that far surpass their proportion of the population. In fact, the rate at which people claim to be the victim of crimes committed by blacks lines up pretty well with how often blacks are actually arrested for violent crime (38). So, for violent crime at least, the different arrest rates seem to reflect differences in ways that blacks and whites behavior. 

Another important source of evidence is a study published in the journal “Personality and Individual Differences” (39). This study, which looked at a sample of several thousand participants of the National Longitudinal Study of Adolescent Health, found that the difference in the likelihood of black and white males being arrested and incarcerated completely disappeared when the researchers controlled for self reported lifetime violence and IQ. In other words, blacks and whites that are equally violent and equally intelligent have the same chance of being thrown in jail. And this research applies to all crime, not just the violent crime that was covered by the National Victimization Survey. 

Proponents of the theory that our legal system is racist often point to drug arrest rates as their strongest evidence. For instance, a 2013 USA Today article reported on an ACLU study that found that blacks are no more likely to say that they have smoked marijuana than whites are (40). Yet, blacks are arrested at a higher rate than whites are for marijuana possession. The implication, according to the lead author of the study, is that racial bias in the legal system must explain the difference. 

Once again, empirical evidence suggests that the best explanation for the racial disparity in drug arrests is not racism in the legal system but, rather, differences in how blacks and whites behave. 

It is important to note that these studies which show that blacks and whites are just as likely to be drug users are based on self report data. In other words, what they actually show is that blacks are no more likely to admit to being a drug user than whites are. If blacks and whites are equally honest about such things then this isn't a problem. But there is evidence to suggest that this isn't the case. Over the past several decades, criminologists have carried out a multiplicity of studies which tested the accuracy of self report measures of drug use across different populations (41-44). In these studies researchers would ask study participants about their drug use habits over the past month(s) and then compare it with the results of tests of the participants urine or hair which would pick up biological residue from the drugs that they had used in the last month(s). What these studies consistently found was that blacks under-report (lie about) their drug use more than whites do. Given the fact that blacks are more likely than whites to falsely deny using drugs, the fact that blacks and whites are roughly as likely to admit to using drugs actually implies that blacks use drugs more often than whites do. 

Additional evidence comes from data collected by the US government on emergency room visits. Self report surveys of drug use normally suggest that blacks make up something like 10%-15% of drug users. Yet, they make up far more than 15% of drug related emergency room visits (45). As covered previously, in 2009 blacks made up 31% of drug arrests. In 2011 blacks made up 30% of drug related emergency room visits (45). Thus, the proportion of drug related emergency room visits that blacks make up is highly similar to the proportion of drug related arrests that blacks make up. Of course, this is exactly what we would expect if the black drug-arrest rate accurately reflected the black drug-use rate. 

But let's say that this evidence didn't exist and that blacks and whites really were just as likely to be drug users. Would that imply that racism is needed to explain the racial disparity in drug arrest rates? A report issued by the Bureau of Justice Statistics suggests otherwise (46). Based on an analysis of survey data collected by the Department of Health and Human Services, the report suggests that there are at least 3 important differences in the ways that black and white drug users use drugs which are relevant to how likely they are to get arrested. The first difference is that black drug users use drugs more frequently than white drug users do. For instance, among black drug users it was found that 32% admitted to using drugs weekly compared to just 20% of white drug users. This difference is obscured by simple surveys that ask participants if they are drug users but fail to ask how frequently they've used that drug. And this difference in frequency of drug use should have an effect on arrest rates: the more you often you commit a crime the more likely you are to get caught committing that crime. The second difference the report listed is that black drug users tend to use drugs which are more likely to get them caught than the drugs white drug users use. For instance, heroin and cocaine users are arrested at roughly 4 times the rate that marijuana users are. And 20% of black drug users claimed to use heroin or cocaine compared to just 16% of white drug users. This disproportionate use of more dangerous drugs will put blacks at an elevated risk for being arrested even if, on the whole, blacks are no more likely to be drug users than whites are. Finally, the report notes that there is an important difference in where black and white drug users use drugs. Blacks tend to live in urban areas which, due to the high levels of violence in black urban areas, have higher levels of police concentration than the areas where whites live. Naturally, the more police that are around the more likely you are be to be arrested. Thus, there are at least three good reasons for blacks to be arrested more often than whites for drug use even when blacks are no more likely to be a drug user than whites are. 

The second way that racism might cause the racial crime gap is by causing blacks to commit more crime. Two pieces of data make this explanation unlikely. First, over the past century racism in this country has decreased. So, if racism causes the B/W crime gap, then the B/W crime gap should have decreased over the past century aswell. But the B/W crime gap has actually increased (47). Secondly, black nations around the world have much higher crime rates than white nations do (48). It seems unlikely that racism can explain why blacks commit so much crime in their own countries. And even if racism did explain part of the association between race and crime that wouldn't exclude the possibility of genetics playing an important role aswell. 

Race, Genes, and Crime

Recall that the B/W crime gap is an international phenomena and that racial differences in behavioral misconduct are present even as early as preschool. These facts alone make genetics a highly plausible explanation for the B/W crime gap. After all, one of the only things that black people have world wide and at all ages are the genes that make them black. The plausibility of a genetic explanation is increased even further by the fact that many environmental explanations of the gap, such as racism and poverty, are inconsistent with the available evidence. And the idea that genetics plays a role in the B/W crime gap is supported by more than this circumstantial evidence. There is also a good deal of direct evidence in its favor. 

The most well established example of this concerns an enzyme called Monoamine Oxidase A. This enzyme breaks down certain chemicals that neurons in the brain use to communicate with each-other. The gene that produces this enzyme comes in a number of different versions. Some of the versions lead to lower levels of MAOA than others. Those that are associated with lower levels of MAOA are often grouped together and called MAOA-L. A recent meta-analysis of over 30 past studies showed that men who posses an MAOA-L gene are substantially more aggressive than men who posses other versions of the MAOA gene (49). A past meta-analysis also confirmed the finding that men who posses an MAOA-L gene are much more likely than those who do not posses an MAOA-L gene to posses anti-social personality traits after experiencing a stressful upbringing (50). Years before these gene association studies were carried out a disease called Brunner's Syndrome was identified which is caused by having a genetic defect on the MAOA gene that leads to even lower levels of MAOA than the levels associated with an MAOA-L gene. Many of those who are affected with Brunner's Syndrome have been found to exhibit extremely impulsive and violent behavior (51) (52). Additionally, several studies have altered the MAOA gene present in mice and caused them to produce extremely low levels of MAOA similar to those found found in Brunner's Syndrome (53-55). These studies have found that these genetically modified mice are much more aggressive than regular mice are. Given the relationship between low levels of MAOA and violence, it should be unsurprising that having an MAOA-L gene also increases the chance that you will end up in prison (56). MAOA ties in to race because several studies have found that blacks are much more likely to posses an MAOA-L gene than whites are. Thus, the genetic differences relating to MAOA production between blacks and whites likely explain some part of the racial crime gap. 

Another important genetic contribution to the B/W crime gap concerns the hormones that produce melanin. Melanin is the chemical that causes color in a person's skin. Africans have dark skin because they posses far more of it than white people do. And they posses more of it than whites do because they posses a greater quantity of the hormones that produce melanin than whites do. Some have posited that these hormones do more than just produce melanin: they also cause some sort of chemical change that causes an organism to behave more aggressively. There are two major sources of evidence for this claim. First, it has been found that dark skin is associated with aggressive behavior in dozens of animal species besides humans (57). And skin shade has been shown to predict violent crime in human populations at the state and national level (73). Secondly, there have been experiments with some animals which have shown that injecting an animal with these hormones actually causes them to behave more aggressively (57). Given that dark skin correlates with aggression across the animal kingdom, melanin producing hormones cause at least some animals to act more aggressively, and dark skinned humans are more violent than light skinned ones, it doesn't seem like much of a leap to say that the high levels of melanin producing hormones present in blacks probably explain some part of their relatively high violence rates. 

Another biological difference between the races, which may or may not be genetic in origin, concerns testosterone. Meta-analyzes show that testosterone is correlated with aggression among humans and non human animals (58). Women who suffer from a disease known as congenital adrenal hyperplasia are exposed to abnormally high amounts of testosterone and are abnormally aggressive (59). And artificially increasing the amount of testosterone in a persons,  or animal's, blood has been shown to lead to increases in their level of aggression (60) (61) (58). In fact, a study of Rhehus monkeys found that injecting female fetuses with testosterone caused them to behave just as aggressively as young males (62). Thus, testosterone appears to cause people to act aggressively. And multiple studies have found that blacks have higher blood levels of testosterone than whites do (63-66). As I said, this difference isn't necessarily caused by genes, but it is clearly biological. 

There is also a clearly genetic component to race difference relating to testosterone. Testosterone effects cells by binding to what is called an androgen receptor. The genes that produce androgen receptors come in different forms. And some of those forms, which are called low repeat versions of the gene, have been shown to cause testosterone to have a greater effect in certain contexts. And multiple studies have found that blacks are more likely to have a low repeat version of this gene than whites are (74) (75) (76). So blacks not only have more testosterone than whites but may also be effected by a given amount of testosterone more than whites are. And this is clearly for genetic reasons.  

This isn't to say that all of the B/W crime gap is caused by genes. Environmental differences between the races no doubt play a role as well. And there is still much to learn about the role that genetics does play. But denying that genetics plays any significant role, which is the race realist position, is to disregard all the available evidence on the topic. 

Conclusion

Hopefully it is clear by now that race realism is not based on un-peer reviewed pseudoscience. The claims of race realists are based on scientific evidence. Of course, each piece of evidence can be disputed. But claiming that a vast, peer reviewed, empirical, literature doesn't exist on the topic is simply wrong.

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27.http://quickfacts.census.gov/qfd/states/00000.html
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29.http://www.theguardian.com/society/2010/oct/11/black-prison-population-increase-england
30.http://link.springer.com/article/10.1007%2FBF02693291
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32.http://www.nytimes.com/2012/03/06/education/black-students-face-more-harsh-discipline-data-shows.html?_r=0
33.http://www.cbsnews.com/news/education-department-black-preschoolers-more-likely-to-be-suspended/
34. http://www.unz.com/article/race-and-crime-in-america/
35. http://www.colorofcrime.com/colorofcrime2005.pdf
36.http://search.proquest.com/criminaljusticeperiodicals/docview/194775428/fulltextPDF/13F966D028A7BE2828D/2?accountid=14787 
37.http://psychology.uwo.ca/faculty/rushtonpdfs/P&E%20Crime.pdf 
38.http://www.amren.com/wp-content/uploads/2011/12/2005-Color-of-Crime-Report.pdf?208409
39.http://www.sciencedirect.com/science/article/pii/S0191886913000470
40.http://www.usatoday.com/story/news/nation/2013/06/04/race-marijuana/2389677/
41.http://informahealthcare.com/doi/abs/10.3109/10826087709027235?journalCode=sum
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44.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3455900/pdf/11524_2006_Article_433.pdf
45.http://ordnungsokonomik.tumblr.com/post/101191677269/racial-bias-in-the-war-on-drugs
46.http://www.bjs.gov/content/pub/pdf/rdusda.pdf
47.http://www.pewresearch.org/fact-tank/2013/09/06/incarceration-gap-between-whites-and-blacks-widens/
48. http://www.jstor.org/discover/10.2307/27503811
49.http://www.ncbi.nlm.nih.gov/pubmed/24902785
50.http://www.biologicalpsychiatryjournal.com/article/S0006-3223(13)00412-5/pdf
51.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1682278/

52.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3738825/
53.http://www.ncbi.nlm.nih.gov/pubmed/7792602
54.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3435113/pdf/nihms-400240.pdf
55.http://www.ncbi.nlm.nih.gov/pubmed/17441000
56.http://www.sciencedirect.com/science/article/pii/S0191886912004047
57.http://www.ferris.edu/isar/bios/rushton/rushton-last-article.pdf
58.http://www.sciencedirect.com/science/article/pii/S135917890000032X
59.http://dare2.ubvu.vu.nl/bitstream/handle/1871/26551/187520.pdf?sequence=1 
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61.http://www.sciencedirect.com/science/article/pii/0376871695011927 
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65.http://www.ncbi.nlm.nih.gov/pubmed/19639516
66.http://www.ncbi.nlm.nih.gov/pubmed/11586501
67.http://link.springer.com/article/10.1023/A%3A1014572602343#page-1
68.http://link.springer.com/article/10.1023/A%3A1016313718644
69.http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0032840 (Table 3S)70.https://www.youtube.com/watch?v=_Oq4xNDBN28&list=UUc7E9A4P_HhiuZMabGrCX5Q

71. Arthur Jensen, The G Factor: the Science of Mental Ability, Pg. 442

72. http://onlinelibrary.wiley.com/doi/10.1002/per.799/abstract

73.http://pdf.k0nsl.org/R/Rushton%20Materials/Templer%20%26%20Rushton%202011%20Intelligence.pdf
74.http://jco.ascopubs.org/content/20/17/3599.full.pdf
75.http://cancerres.aacrjournals.org/content/55/9/1937.long
76.http://www.hindawi.com/journals/pc/2013/763569/

(Source: spawktalk.blogspot.com)