[creatonez]

> I even read a post recently here in HN where it was said that "Urban humans have lost much of their ability to digest plants"

This story is interesting, but doesn't shock me a whole lot from the perspective of losing our touch with nature, because we now have an understanding that our ancestors fluctuated between carnivory and herbivory quite a lot. If these population changes in gut bacteria can be caused in such a short span of time, it seems likely that it can also be reversed.