Tailbone
What are the religious answers for the purpose of the tailbone in the body? Science will tell you that it is an indication that we once had a tail and evolved. Of course many religious groups do not believe we evolved, but instead came from Adam or other starting point. Therefore why would God give us a tailbone?
I believe it is to signify where the back ends and where the "backside" ends. I don't know of any religious reasons for it.
You mean where the backside "begins"? Interestingly enough the tail bone is fixed to one side of your butt. You can know which side if you have an accident there or feel for it. I cannot see any reason for that in the realms of creation. Must be an added 'feature' to give rise to the thought of evolution?