An animal that can regrow its entire body

WHEN A PERSON loses a limb it is a life-changing tragedy. For a salamander, it is an inconvenience, for the limb will soon grow back. Distantly related animals from gastropods and arthropods to lizards and amphibians all possess the ability to regenerate lost body parts. Some can ditch their extremities when they become infected or injured, a process known as autotomy.Researchers have long been interested in these regenerative powers. Some hope that unravelling the biological mechanisms underlying them might one day have medical applications in humans. Now, though, a pair of biologists have turned up the most drastic example of regeneration so far. A paper in reports two species of sea slug that are capable of jettisoning their bodies below the neck, and then building new ones from scratch.