Change the default contact owner?

Change the default contact owner?

As it stands today, when you click add new contact, my name is the default contact owner. What I want to do is force our sales reps to choose their own name from the list. While I can instruct people to do this, only a handful will probably listen, so I or someone I anoint will need to go in and make updates. 

How can I change the default contact owner from my name to either blank (to make them change it) or something like "select your name"?

Thanks!

John Galich