Researchers at Japan’s Nara Women’s University have discovered a new trait exhibited by the sacoglossan sea slug – it has the ability to decapitate itself, then regrow its body. The process, from shedding all of itself below the neck to regrowing a new body, takes less than a month, in an extreme example of a process known as autotomy

• Keep your head: the self-decapitating sea slugs that regrow their bodies – hearts and all