Regenerative medicine is the study of methods that can help regrow a damaged limb or organ, and it has always seemed like science fiction…until recently, that is. Scientists at the Salk Institute have found one of the clues to the puzzle. They’re studying zebrafish, which can regrow their tails, to find out what triggers the regeneration and how it is controlled. What they’ve found so far is very promising, and could lead to medical advancements that could make prosthetic limbs and organ transplants history.