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.

Once upon a time a myth was born that insects, unlike animals, are just a machines that not capable of learning and survive only based on their instincts. That myth has become the widespread opinion. Of course, this opinion is indeed erroneous, like many other widespread opinions. Let us try to find out which part is a myth and which part is true.

Tanzania, 1964. A touching moment between primatologist and National Geographic grantee Jane Goodall and young chimpanzee Flint at Tanzania's Gombe Stream Reserve. (Photo by Hugo van Lawick via National Geographic)

Steve McCurry has been a photojournalist for over 30 years. He is the recipient of the Robert Capa Gold Medal, the National Press Photographers Award and four first prize awards in the World Press Photo contest. Photo: Afghanistan. (Photo by Steve McCurry)

Bikini-clad women sit as they operate a 3.6 metre-high custom-made female robot at the “Robot Restaurant” in Kabukicho, one of Tokyo's best known red light districts, August 15, 2012. (Photo by Tokyo Scum Brigade)

Nino, a ten-year-old toreador apprentice of the French Tauromachy Centre, nicknamed El Nino, touches a practice bull at the bullring of Garons, near Nimes, September 25, 2013. Since 1983, the French Tauromachy Centre in Nimes has trained some 1,000 youths in the art of bullfighting. Twenty of them have gone on to become professional matadors, facing fighting bulls in the arena. Twice a week, students take courses with a matador to learn the movements and gestures of the bullfighter in the ring, but without an animal present. Students train with calves in the surrounding fields during spring, and regularly participate in beginner's bullfights (becerradas) without killing calves. Solal has been taking courses for three years and Nino, for just a year now. Both are normally enrolled in French public schools, but have one thought in mind – bullfighting. They share a passion linked to the city of Nimes, famous for its ferias and bullring. (Photo by Jean-Paul Pelissier/Reuters)

Members of an American landing party assist troops whose landing craft was sunk by enemy fire off Omaha beach, near Colleville sur Mer, France, June 6, 1944. REUTERS/Weintraub/US National Archives

A man standing on the first cables during the construction of the Golden Gate Bridge with the Presidio and San Francisco in the background, San Francisco, California, 1935. (Photo by Underwood Archives/Getty Images)