Monthly Archives: November 2011

Picojonah Meets Microwhale


Colpoda is a common freshwater ciliate genus.  It is usually associated with moist soils and grasses.  First et al (2011) show the bacteria Campylobacter jejuni resists digestion by Copoda; to point that live bacterial cells are egested (not quite pooped, not quite puked).  Campylobactor jejuni is the leading cause of gastroenteritis.  I am sure that there is a micro-to-meso scale Leviathan out there for Colpoda, but that is different issue. The authors suggest the ciliate might act as a reservoir for the bacteria.

I have to wonder how common this is; could there be other advantages to surviving a digestive adventure.  First et al site papers that describe amoeba that pass live bacteria that actively resist their own digestion.  However, a couple of other examples come to mind.  Many fruit seeds pass through the digestive tracts of birds and other organisms.  This is the whole point of fruit; in exchange for a nice snack the plant gets its offspring dispersed farther than it would be possible otherwise.  Parasites like guinea worms must be ingested to survive and reproduce, and only leave the host for dispersal.  A percentage (about 15%) of Japanese land snails that are eaten by birds are still alive when “released.”  Dispersal is offered as an advantage for the snails but is seems like that might be a side effect of just making it out.  Of course, Luke, Jonah and Geppetto were spit up by their consumers through some action (their own or others).  Is Campylobacter: finding a refuge, using the ciliate as a dispersal agent, just riding out digestion like a snail, or are they Jedi?

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