In Afghanistan -- as in military conflicts going back centuries -- dogs play myriad roles, from companions and pets to scouts and, increasingly, living, breathing land mine and IED (improvised explosive device) detectors. Sgt. John Barton of the 4th Brigade of the U.S. Army's 82nd Airborne Division greets his platoon's pet dog, Ray-Ray, at combat outpost Impala in Bala Murghab, Afghanistan. Corporal Dave Heyhoe, of the British Army Theatre Military Working Dog Support Unit, and his dog Treo and Royal Army Veterinary Corp Lance Cpl. Marianne Hay, and her arms and explosive search dog, Leanna, rest in the village of Segera, Kandahar Province, Afghanistan. Marines of 3rd Battalion, 6th Marines, give cereal to a stray puppy in northern Marjah, Helmand province, southern Afghanistan.