"Eisenia fetida … can regenerate after multiple amputations. We know this because researchers have cut the same segments off five or six times and watched them regenerate each time. Some worms have even suffered thirty or forty amputations and regrown segments.
This phenomenon has led some researchers to experiment with transplanting heads or tails from one worm onto another. Like circus animals, the worms oblige and continue to perform. You can cut a tail off and suture it to the head of another worm, and within a couple of weeks, the intestines and nerves will join together and work properly, even if the two ends are rotated at a forty-five-degree angle to one another and then joined. You can take a head from one, a tail from another, and a middle section from a third, suture them all together in the correct sequence, and get one complete worm. Two worms can be stitched together side-by-side, like conjoined twins, and soon they’ll grow together and function normally. I’ve even heard that the first and last segments of a worm can be nicked off and head and tail joined together, so that the worm forms an O. (Admittedly, the worm would not live long in the shape of infinity, with no ability to eat or excrete castings.) The tails from two different worms can be sutured together and the resulting creature can live quite a while, but a worm made from two heads will never be quite right and won’t live long."
Kylee Baumle is the author of the popular gardening blog, Our Little Acre and is a feature writer for Indiana Gardener magazine. She is also the Book Review Editor for Horticulture magazine. She lives and gardens in rural northwest
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