Military working dog Rex soaks in the loving scratches from his handler, Myke Erdmann, in between vehicle searches May 14, 2012. The pair, along with handler Joshua Billig and his parnter Dennis, searched vehicles and luggage entering the base. All four work with the Combat Center's Provost Marshal's Office. (Official USMC photo by Sgt. Heather Golden / Released) - Military working dog Rex soaks in the loving scratches from his handler, Myke Erdmann, in between vehicle searches May 14, 2012. The pair, along with handler Joshua Billig and his parnter Dennis, searched vehicles and luggage entering the base. All four work with the Combat Center's Provost Marshal's Office. (Official USMC photo by Sgt. Heather Golden / Released)