Why do you put pins on them?

We have a history of poking things in holes, of putting fingers into and through holes — orifices and others, of prizing through sphinctea, of playing with (caressing, fiddling, twisting, wringing) our own fingers, as well as those of others. Apparently, a long history.  Apes do it.   As things with finger sized holes, rings insist that we engage with that history. What is a ring without a finger?  What is a finger without a hole?