A little while back, we received a classic question about worms, one that most of us have probably been hearing since we were quite young: if you cut a worm in half, will it survive? (A common variant of the question: when you cut a worm in half, will you be left with two living worms?) The reader specifically asked about the regeneration of worms that are cut in half in the course of gardening (accidentally, we should add), so it is likely our reader is wondering about earthworms, that ever-present companion to gardeners (at least if your garden is healthy). So, the precise question we are interested in is whether an earthworm, when cut in half, will regenerate.