Thought it was an interesting question to be honest... I'm fine with the occasional article asking a question without immediately providing answers. It makes a

Thought it was an interesting question to be honest... I'm fine with the occasional article asking a question without immediately providing answers. It makes a strong case for the gap to actually exist (which has been contested in the past), by showing studies unaffected by immigration which still indicate a gap. And it also offers some answers. The most compelling one is that it's cultural, behavioural, relating to diets, smoking, drinking etc. The argument for this is that the gap is smaller for immigrants who are 2nd, 3rd generation, and who have assimilated more of the typical US culture.