Join Date: Dec 2001
Location: Belleville, Illinois
Thanked 22 Times in 17 Posts
I think that garden variety worms can grow a new end. IIRC the part with the band can regenerate the rest, but the part without the band is a goner. When severed it will thrash around attracting the predator so that the rest can escape.
I think that it's flatworms that can be cut in two and both pieces will live long and prosper, but only if you split them down the middle. Cut a flatworm brain in two and pretty soon you have two flatworm brains, for whatever that's worth. Golly, it's been a long time since I took high school biology.
Starfish can also do that trick. I've heard of clam and oyster fishermen chopping starfish into pieces because they eat bivalves. But that just makes matters worse - every piece can grow into another hungry starfish.