Good reason exists to doubt whether genes advantage black Americans at sport as Jon Entine claims -- the phenomena of the birthday or age cut-off effect. There is nothing genetic about being born in August rather than September but it can profoundly change the odds on becoming a professional footballer or tennis player [as well as being treated for mental sub normality or dyslexia]. The cut-off effect shows that big population differences need not be …showed first 75 words of 868 total…

…showed last 75 words of 868 total…has shown strongly effect what we achieve see Bandura, A. (1982). Self-efficacy mechanism in human agency. American Psychologist, 37, 122-147. This is not to deny the possibility of a superior genetic ability in black Americans in sport: only that citing population statistics is without meaning. The real science must involve analysis at the individual level in terms of anatomy and physiological traits, sporting success, and degrees of African ancestry [a factor that varies markedly between black Americans].