Yes i have read similar medical articles as well. I also came across one (can't find it now) that talked about how recent teenage pregenacy increases and gangs are linked to the fact that children are now going through puberty quicker and the frontal cortex which controls are decisions hasn't full developed which means men take risky decisions when they can't fully handle things which is no suprise. Yes also i read that black people have higher testesterone because its down to evolution in this way... i believe there was a study done in africa i forgot the country.. but basically one society it was a warrior society men had to pass trials and other things to pick the best women etc.. and the other society was structured around farms. Basically the one which was a warrior culture had far higher testesterone because only the strongest men were allowed to reproduce. Now if in the times of slave trade we brought people over that had that, then this would make perfect sense. It also is amazing how europeans and asians are actually different to black people but yet, never much is talked about this because it is deemed not politically correct 1-2% of european DNA is thought to be neanderthal.