Got Mandarin troubles? Blame your parents. If they'd had the sense to be Asian before you were born, then you might be picking up on your tones a bit quicker.
Says Prof Robert Ladd of Edinburgh University:
we suggest that there might be something that would make it easier or more natural, in some way we don't understand, for an individual to learn and use a tonal language than a non-tonal oneHowever, my kids should be ok...
Not that I'm calling my infant or toddler normal.
It remains true that any normal human infant will acquire the language of any community in which it's raised, regardless of its genetic makeup.