That purpose may be "kill the old to make sure the world keeps changing, make sure new genetic experiements (ie. kids/offspring) get a chance". As we hopefully

That purpose may be "kill the old to make sure the world keeps changing, make sure new genetic experiements (ie. kids/offspring) get a chance". As we hopefully all know, nature isn't afraid to kill off a few people to get more useful experiments (how many animals die trying to have sex, for instance. That is not "necessary") Early animals didn't age, nor did they die. Some plants don't age (they still die due to illness or trauma, but not through old age). Even "mortal" animals today are offshoots of a central cell-line that doesn't age (ovi in women get their age reset upon birth then no longer age. Sperm get their age reset upon production. This goes for all animals that age, not just for humans). So you are immortal, in the sense that some of the cells that form part of your body won't age and die like the rest of you.