They do have piercings, which argues that not everything gets shoved out/reset. That argues that something like a piercing or tattoo that's designed to take advantage of the body's natural healing might stick around for a while. And they can clearly shave and get haircuts, so their body hair doesn't automagically regenerate every time they die.
I'm not sure where circumcision falls on this scale, though!
Re: Joe/Nicky, circumcision
I'm not sure where circumcision falls on this scale, though!