According to neurohormonal theory, prenatal androgens are key determinants of sexual orientation. As a reputed marker for prenatal androgens, the 2D:4D finger length ratio has been used in more than a dozen studies to test the hypothesis that prenatal androgens influence sexual orientation. Findings have been very inconsistent.
To date, international comparisons of self-reported crime have been mostly limited to Western countries. The current study explores offending for large samples of university students in Malaysia (N = 2,058) and the United States (N = 2,511), and utilizes measures of social bond theory to test its predictive utility cross-nationally. The descriptive results reveal that for both males and females, offending rates were substantially higher in the United States, often 3 to 4 times higher. Rare events logistic regression results reveal not only some support for our measures of the social bond constructs in both countries but also that there are significant cross-country differences in the correlates of offending. Partitioned regression models suggest these differences vary considerably by type of crime, and that some of the significant correlates of offending are similar cross-nationally but that unique predictors emerge by country dependent on the offense in question. Offending in the U.S. sample appears to be more closely linked to breakdowns in family structure (parental divorce, single parenthood), whereas for the Malaysian sample, parental income and respondent's education level seem to be more closely linked to offending. The current study provides one of just a few comparative studies between a Western country and an Asian country based on self-reported data. Such data can provide a useful cross-check of international comparisons based on official data. Methodologically, implications are that the self-report survey method continues to be a fruitful avenue for exploration of cross-national offending.
Beginning early in fetal development, the androgen receptor (AR) gene helps regulate bodily exposure to testosterone. Most studies of individuals have found an inverse correlation between the number of CAG repeats on this gene and serious forms of physical aggression. This two-phased study was primarily undertaken to determine if a link between AR CAGn and physical aggression also exists at an ecological level of analysis. To make this assessment, we first conducted a bivariate analysis of the average number of AR CAG repeats for a large number of countries and the rates of crime victimization in those same countries. Except for motor vehicle theft, as the national average number of CAG repeats increased, crime victimization rates decreased. This inverse relationship was especially strong for violent offenses. In the second phase of this study, we sought to determine if per capita gross domestic product, pathogen prevalence, and average intelligence might be mediating some of the AR CAG repeats-criminality relationship. Mediation analysis analysis indicated that, once gross domestic product and pathogenic prevalence were controlled, average intelligence was able to eliminate most of the links between CAG repeats and crime victimization rates, especially in the case of violent offenses. These findings suggest that the AR gene is not influencing criminality primarily by altering testosterone brain exposure (as we suspected). Instead, it may affect criminality mainly by affecting cognitive ability. In fact, once average national intelligence is included in the mediation analysis model, direct relationships between CAG repeats and measures of homicide, assault, and robbery were no longer statistically significant. Findings from this two-phased study point toward the AR gene as having multiple effects on brain functioning, particularly regarding intellectual development as hypothesized by Manning [62]. Replication is obviously needed.
General theory attributes criminal behavior primarily to low self-control, whereas evolutionary neuroandrogenic (ENA) theory envisions criminality as being a crude form of status-striving promoted by high brain exposure to androgens. General theory predicts that self-control will be negatively correlated with risk-taking, while ENA theory implies that these two variables should actually be positively correlated. According to ENA theory, traits such as pain tolerance and muscularity will be positively associated with risk-taking and criminality while general theory makes no predictions concerning these relationships. Data from Malaysia and the United States are used to test 10 hypotheses derived from one or both of these theories. As predicted by both theories, risk-taking was positively correlated with criminality in both countries. However, contrary to general theory and consistent with ENA theory, the correlation between self-control and risk-taking was positive in both countries. General theory's prediction of an inverse correlation between low self-control and criminality was largely supported by the U.S. data but only weakly supported by the Malaysian data. ENA theory's predictions of positive correlations between pain tolerance, muscularity, and offending were largely confirmed. For the 10 hypotheses tested, ENA theory surpassed general theory in predictive scope and accuracy.