Does eating trees make you termitier than the sword?
Imagine one day as you’re reading or eating a book, your house is suddenly ripped apart in an untimely predation event, because your house is a termite, and before you can scramble away with your flagella in search of a new termite-house, you’re paralyzed by a huge blob of tree goo. I know, I HATE when that happens. Then again, that’s how I feel when I wake up sometimes—horrified and immobile—but at least it’s not permanent. Unfortunately for one gang of flagellated friends approximately 10 million years ago, the nightmare was real, and the condition really permanent.
Luckily their sacrifice did not go unrecognized (Memorial Day reference!). Scientists from Oregon State University reported Friday the discovery of what is now the the oldest example of a cooperative symbiosis (a “mutualism” if you will) between an animal and a microbe. The story is extra cool because it’s based on ”there it is!” observable-with-your-eyes evidence: in a piece of amber (tree resin of the past/not the ’90s singer of the past), a termite’s gut was preserved just after it was ripped open, revealing the symbiotic protozoans inside. (Many new genera were described, but the press picked only the one with the picture, Microrhopalodites, to mention.) The discovery highlights how organisms have been engaging in cooperative symbioses and co-evolution for a really, really, long time (“really, really” is a technical term that means, um, about 10 million years). Relationship status: It’s complicated with Microrhopalodites.
As a coral biologist, I of course think animal-microbial mutualisms are The Ish (all up in here). But mutualisms can be pretty tenuous; cooperation can turn to cheating, and the cheatee will often end the relationship, even if both parties suffer. This happens to corals whose symbiotic algae (So in love with you/It’s too good to be true) get out of control thanks to increased temperatures, or sediment, or fertilizer, or bacteria… or all of the above (PS, coral reefs are dying). The algae get selfish, make a big metabolic mess, and the cranky coral says “later, loser symbiotic dinoflagellates.” (I’m letting you go/But I won’t let you know.) Sadly, after sticking up for itself, a bleached coral often dies.
Our sappy termite story is even more tragic because the protozoans in the amber didn’t do anything wrong. This symbiosis ended not due to poor cellulose-dissasembly on their part, but by the brute force ripping apart the gut of their insect host. (Chopped and screwed.) If you ever get stuck in tree sap while your relationship literally falls apart around you, know that your last moments may be forever preserved for the good of science, like, a bazillion years later.
A Microrhopalodites protozoan mourns its breakup
My favorite thing about this story—no, not the fact that I can add Microrhopalodites to my lexicon—is that the author of the study, Dr. George Poinar Jr., is an “international expert on life forms found in amber.” Props to academia for supporting awesomely specialized expertise like that. The cynic in me is pretty sure no one in the 2009-2010 professorship recruiting class will be able to frolic scientifically within such a narrowly-defined field of study without selling it as—and researching on the side—cancer therapy or something. Science is almost always spun as applied or nearly-applied these days. Otherwise, kiss your funding chances goodbye. (Scientist-Granting Agency mutualisms: NSF, I promise to love you forev-xactly 12 more months.) A nice argument for the importance of free-reign, open-ended research was written by physicist Stephen Quake at Olivia Judson’s New York Times blog earlier this year.
I should point out that my least favorite thing about this story is that now I’m going to have nightmares about running in slow motion while being chased by tree resin (to a ’90s dance music soundtrack in all likelihood). Given the current state of my mutualisms, I probably won’t feel a lot better when I wake up.
Posted in Discovery, Evolution
