When it was revealed that Atrians and Humanas could successfully procreate the first thought that came into mind was how the Atrians are doomed as a species. From what I can tell there isn't a lot of them. At most I would say 10,000 and I think that estimate is generous. The Atrians are simply going to be absorbed into the human populace in time. It will most likely take a hundred years give or take how long it takes for Atrians to become fully integrated into human society. But once that happens more and more atrian/human pairings will happen. Within 200 - 300 years I think there will no longer be any pure-blooded atrians and within 500 years there will only be a very small percentage of the population that would have any definable atrian traits.