Smallest bacteria evah!

Smallest bacteria evah!  With a volume of around 0.009 cubic micrometers, these little beasties are really, really small – about as small, scientists think, as it's possible for a bacterium to be.  How small is that?  Well, a cup would hold about 237 trillion of them.

This got me to pondering just how many bacteria does a typical person have wandering around in their body.  It turns out I'm not the first person to wonder that, and there's a lot of information on the topic out there.  Estimates are that about 100 trillion bacteria live in your typical human.  These bacteria, on average, are much larger than the little beasties just found – and a typical person has about 5 pounds (~2kg) of bacteria in them.  Many of these bacteria are essential for life, not just freeloaders and parasites.  Some, of course, are not so benign.

I knew that my body had a bunch of hitchhikers, but I didn't realize I had quite that many!  And that's just bacteria – things get even crazier when you look at the virus load...