Immortality..

So there's this jellyfish, Turritopsis nutricula. And it can revert it's life cycle to become fully sexually immature (A Polyp) after living to the mature state. In reality, this means it can age backwards and live forever, so long as disease or predators aren't a factor. It's called Transdifferentiation, and means that the cells themselves are modifying to correct and problems with the creature. Salamanders can also do this with their tail structure and also with their Iris cells; reverting into lens cells when lens cells are damaged. They should tap this shit! Imagine a brain that would automatically repair any imperfections to its genetic code.. Mental illness would be eradicated!