Print This image shows the head and the body of Elysia cf. marginata, a day after autotomy. The shed body is much heavier (>80% of the total weight) than the head. Credit: Sayaka Mitoh Advertisement Two species of sea slugs can pop off their heads and regrow their entire bodies from the noggin down, scientists in Japan recently discovered. This incredible feat of regeneration can be achieved in just a couple of weeks and is absolutely mind-blowing. Most cases of animal regeneration — replacing damaged or lost body parts with an identical replacement — occur when arms, legs or tails are lo...