I live in Frankfurt Germany and I experience people smoking crack in public spaces (we used to be a heroin city but giving out free heroin actually has drained the swamp and there’s almost no new heroin addicts). One day on my way home i had on each step from my office door down ...
under these conditions, if you managed to cover a few meters in a few weeks, then you qualify as a low reynolds number swimmer. this clearly isn't a hospitable environment for denizens of our middle world . but yet this is the scale of the task that microbes face simp...