there is a valid medical reason for circumcision, recent medical research supports that uncircumcised guys have a much greater chance of giving their female partners cervical cancer:
http://www.usatoday.com/news/health/...1-cervical.htm
circumcision dates back to the dawn of civilization and was both ritually and practically performed in both the new and old world land masses for thousands of years prior to columbian contact. the ancients may not have had the arsenal of modern scientific technology, but their cultural adaptations generally have practical foundations. as a rule, religion adopts sound practices as ritual in order to perpetuate norms and mores outside of the secular legal structure of the society.