Myomancy ADHD, Dyslexia and Autism

I found an interesting new blog called Retrospectacle written by a PHD student studying the inner workings of the ear. As dyslexia has a strong hearing aspect to it I had a dig around and a couple of posts caught my eye.
The first pointed out a great education site about the ear called Promenade ’round the Cochlea. Lots of clear illustrations and descriptions about sound, the ear and the brain.
The second post is on how melanin gives black people better hearing. Apparently it improves the ability of the hairs in the inner to resist and recover from damage. This caused me to wonder if dyslexia rates are lower in black children than white children. A good dig around on Google failed to shed light on any differences in the rate of dyslexia based on ethnicity but its an interesting question.