Blacks have quite a bit less cranium space than northern eurasians (-10%) . But I am convinced its much more than a real estate issue. Intelligence seems to me to be a set of trade offs. Jews seem to excel at social functions and communication at the expense of mechanical/engineering ability. Chinks are technologically proficient at the expense of ingenuity. Blacks seem to have great musical and rhythmic instinct as well as great coordination and I just think their neurology is really geared that way. They are good at this, whatever this is. This is where their IQ went. It takes neurons to do this. I can’t do this. https://m.youtube.com/watch?v=HgsQdtrpF08 Speciation is kind of arbitrary. Modern humans have ancestors from multiple other “species” within the last 50,000 years. But blacks are certainly genetically divergent enough for it to explain behavioral differences that crop up over and over in every aspect of life.