Fascinating Fact about Planarian Worms

Have you ever heard of planarian worms? These little guys exhibit the remarkable ability to regenerate (like starfish) if you chop them into little pieces.

That in itself is a pretty nifty trick, of course. But what really makes planarian worms seem like something out of science fiction is that — unlike starfish — they regenerate from both pieces. If a starfish loses an arm, it grows a new arm and the other one floats away and dies.

If you chop a planarian worm in half, both halves regenerate what they lost and you get two planarian worms.

And now here’s the part that should really freak you out: Both new worms appear to retain the memories of the original.

In the unlikely (and, of course, horrible) scenario that you had your head chopped off, you might hope that one day “science” would be able to give you a new body and you’d get to keep being you. But you’d probably never even considered the idea of your old body growing a new head and that being you, too.

Swamp ThingA report on NPR a few days ago broke news about how we’ve confirmed that planarian worms do just that. But I don’t understand why this is news now, because I swear I remember reading about (and being amazed by) this magic of planarian worms in a Swamp Thing comic book in the early 80s.

2024-03-19: Broken links in this post have been removed and/or updated.

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