If you’re one of those 18,000 or so people who didn’t get chosen to be in NASA’s next astronaut training program, you may want to wipe away your tears and read this: a flatworm sent into space on a recent mission to the International Space Station came back with two heads! If you think that’s scary, wait until you hear what they did to the poor flatworm first!
“The process of regeneration is normally 100 per cent accurate – they never make two-headed worms in the wild.”
That discomforting comment is from Michael Levin, professor of Regenerative and Developmental Biology Morphological and behavioral information processing in living systems at Tufts University in Massachusetts (his business card must be huge) and co-author of a paper on the experiment published this week in the journal Regeneration. The experiment began in January 2015 when a number of flatworms were sent to the ISS on the SpaceX Commercial Resupply Service Mission 5. Some of the worms were whole, but one … you may want to stop eating lunch before reading this … had both its head and tail cut off. Those sick b*stards!
Don’t get back to eating just yet. The piece of flatworm sent to the ISS what flatworm researchers call a “pharynx fragment,” which means it was just a mouth or pharanx leading to the digestive tract in its belly. When this is done on Earth, the pharynx fragment eventually regrows its head and tail to become a normal flatworm again. Not in space. Instead, this fragment grew two heads with the second having its own functioning mouth.
At this point, you may want to just skip lunch altogether.
“Remarkably, amputating this double-headed worm again, in plain water, resulted again in the double-headed phenotype. Moreover, even when tested 20 months after return to Earth, the space-exposed worms displayed significant quantitative differences in behavior and microbiome composition.”
That’s right. When their two heads were cut off on Earth, two more heads grew back every time for well over a year. And all of these mutants suddenly began avoiding dark spots in their Petri dishes. What’s THAT all about?
Of course, the researchers optimistically see their beakers as half-full, explaining that this space-caused regeneration would be studied as a possible method of someday treating astronauts for injuries or amputations in space.
However, future space travelers may want keep their helmets on and avoid cranial injuries. Based on the experience of these flatworms, in space, no one can hear either of your heads scream.