Modern city dwellers have lost about half their gut microbes
This article is mostly cliche popsci trash that isn’t worth reading.  Good for a game of logical fallacy bingo.The only interesting development seems to be the methodology but that only gets a passing mention.The rest is basically fearmongering.> In humans, for example, gut bacteria influence how the immune system responds to pathogens and allergens, or interact with the brain, affecting mood.Ok.  But what does that have to do with diversity?  Humans have not been an emotionally rational species at any point in the past.  Arguably the relationship between gut biome diversity and civilization is inverse.  Maybe we want fewer microbes.Lifespan has also increased with decreased gut biome diversity.This is why correlation alone is uninteresting.  You can find it anywhere.> Splitting the difference, people in less developed parts of the world have between 60 and 65 of those bacterial groups, an observation that ties the decrease in microbial diversity to urbanization.Oh come on.  How does a line like this get published?  This is fine if you define “ties” as “moves with” but not “is connected to”.  IOW correlation doesn’t imply causation.> Kyle Meyer, a microbiologist at UC Berkeley, argues such losses are not necessarily a problem. “Maybe we don’t need them,” he points out. But Moeller is worried. “We are really doing some scary stuff to our microbiomes,” he warns.Why is it “scary”?  Nothing in this article established any cause for concern.The guy that developed the methodology is now in search of a problem his solution fits.