A genetically engineered featherless rooster struts around the campus of the Hebrew University of Jerusalem's Department of Agriculture May 22, 2002 in Rehovot, Israeli. After two years of research, departmental scientists announced the naked chicken, as it has been dubbed, as a low calorie bird because the lack of feathers means the chicken has less fat. It also matures earlier than its feathered counterparts. (Photo by Moshe Milner/GPO/Getty Images)

Dr. Hannah Cobb from The University of Manchester looks at a viking sword during a viewing at CFA Archaeology of artefacts discovered from the first fully intact Viking boat burial site on October 18, 2011 in Edinburgh, Scotland. (Photo by Jeff J Mitchell/Getty Images)

Irene Aguirre, 23, attends a boxing class at the National Institute of Sport in Managua March 4, 2015. A study done by the Psychology alumni of the National Autonomous University of Nicaragua (UNAN-Managua) revealed that about 1 million women in Nicaragua suffer from domestic violence. (Photo by Oswaldo Rivas/Reuters)

Throughout the course of the long war in Afghanistan, Coalition troops have relied on thousands of military working dogs to help keep them safe, and make their jobs easier. The dogs are trained to detect explosives, to find illegal drugs, to search for missing comrades, or target enemy combatants. Not only are they active on the front lines, but behind the lines they serve as therapy dogs, service dogs, and loyal companions. They also share the same risks as the ground troops, suffering injuries and sometimes death on the battlefields. Gathered here are images of these dogs and their handlers in Afghanistan and back home, from over the past several years, part of the ongoing series here on Afghanistan.

Casket of Leibby Kletzky, a murdered eight-year-old boy who went missing from the Hasidic neighborhood of Borough Park, Brooklyn is carried during a procession on July 13, 2011 in New York City. After a two day search Kletzky's dismembered body was found partially in a suitcase inside a dumpster and partially in a refrigerator in a nearby apartment. Police detectives have taken Levi Aron, 35, into custody in connection to the killing. (Photo by Ramin Talaie/Getty Images)

A Somali police officer arrests a suspected rebel member of the al Qaeda-affiliated al Shabaab among beach goers in Mogadishu. Al Shabaab claimed responsibility for today's pre-dawn attack on a Kenyan university campus near the Somali border. The following gallery examines who is al Shabaab. Here: Somali police officer (R) arrests a suspected rebel member (L) of the Al Qaeda-affiliated al Shabaab among beach goers at the Lido beach north of Somalia's capital Mogadishu March 23, 2012. (Photo by Feisal Omar/Reuters)

A humanoid robot named Kansei, meaning “sensibility” in Japanese, makes a facial expression depicting “happiness”, next to the word “Love” during a demonstration at a laboratory of Meiji University's Robot and Science Institute in Kawasaki, south of Tokyo in this June 4, 2007 file photo. Three-fourths of robot installations over the next decade are expected to be concentrated in four areas: transportation equipment, including the automotive sector; computer and electronic products; electrical equipment and machinery. Labor costs have climbed in countries such as China that have been popular for outsourcing production, while technological advances for robots allow them to be more flexible and perform more tasks. (Photo by Yuriko Nakao/Reuters)

Individuals and populations student winner. Limbing in the Tropics, photographed in Manaus, Brazil. While walking in the Amazon rainforest looking for bat roosts to set up mist nets to capture bats for scientific research, a faint and almost imperceptible noise suddenly caught this photographer’s attention. An anteater was climbing with exceptional ability in a tangled mess of branches and lianas. (Photo by Adrià López Baucells/University of Lisbon/British Ecological Society)