It came from space! Two-headed flatworm stuns scientists
The regeneration process continues to baffle boffins
A flatworm sent to the International Space Station has sprouted two heads, an anomaly that never happens in the wild, according to a paper published in the journal Regeneration.
Flatworms may not look particularly interesting at first. But lop one to pieces and it’ll magically grow a new head and tail to become a different worm. The regeneration process is well-known, although it is not completely understood.
As if the problem wasn’t hard to solve on Earth, a group of scientists booted 15 headless and tailless planarian flatworms (Dugesia japonica) up to the ISS for five weeks to see how the process was affected by space travel. A control group was kept in spring water on Earth.
One out of the 15 animals managed to rejuvenate two heads, an extremely rare event. Michael Levin, co-author of the paper and professor of Regenerative and Developmental Biology Morphological and behavioral information processing in living systems at Tufts University in Massachusetts, told The Register:
“The process of regeneration is normally 100 per cent accurate - they never make two-headed worms in the wild,” he explained
What’s even more surprising is that even after the ends of the flatworm were chopped off, it always regrew with two heads.
“This two-head state persisted past several rounds of regeneration back on Earth, over a year later after the trip, suggesting that this fundamental change to the animal’s body plan was stable,” Levin said.
Space travel definitely affected the regeneration process, Levin reckons. There are several components including the high G-forces from takeoff, the loss of Earth’s magnetic field, weightlessness, vibrations and stress of re-entry and landing that could have contributed to changing the flatworm’s ability to develop new body tissues.
Extra heads weren’t the only change to the flatworms. Returning specimens were less likely to scoot over to dark areas of a petri dish after particular areas were illuminated – a behavior that persisted for more than a year after they returned to Terra Firma. Analyses also show that their microbiomes and metabolism shifted in space.
Scientists are now trying to work out how space affected the regeneration process. “If we understood how that worked, we could address many pressing needs of regenerative medicine, birth defects, and cancer reprogramming,” Levin said. ®