For the past two years, Rob Dunn has been digging in belly buttons. Normally, this would be frowned upon, but he and his team are doing it in the name of science. So, proceeeeeed, my good man.
The invisible microorganisms that live on and in us outnumber our own cells by at least ten to one. We know shamefully little about how those species, belly button bacteria and otherwise, interact with our own biology. We know perhaps less what species are even in there. So, to find out, Rob Dunn has been sequencing the genomes in as many belly buttons full of bacteria as he can swab.
The biodiversity of the belly button seems to have more in common with forests than fauna. Species that are numerous in one person will be numerous in another, if we share them at all. Likewise, what’s rare in my belly button will be rare in yours, if it happens to live there. But then again, we may have completely different forests altogether in our navels.
And despite the numerous never-before seen species that Dunn’s belly button surveys have turned up, the rabbit (belly button) hole seems to be getting deeper, not shallower.
Why do certain people have certain bacteria in their navels? Age, geography, pets, diet, hygiene … we simply don’t know yet. So I, for one, hope Rob keeps swabbing and sequencing. Innie or outie, maybe we can one day get to the bottom of the belly button?
(I suggest you go read Rob Dunn’s complete story at Scientific American. Image via abriz44 on Flickr and wildlifeofyourbody.org, and apropos of nothing, why the heck does Carl Zimmer have Japanese soil bacteria in his navel?)