In this May 4, 2014 photo, a miner holds an amalgam of mercury and gold he mined after working a 28-hour shift at an illegal gold mining process, in La Pampa, in Peru's Madre de Dios region. Thousands of artisanal gold miners sweat through the long shifts and endure, for a few grams of gold, the perils of collapsing earth, limb-crushing machinery and the toxic mercury used to bind gold flecks. (Photo by Rodrigo Abd/AP Photo)

Layers of breathtaking colour streak the rolling hills of this vast desert, making the landscape appear as though it has been tie-dyed. The natural phenomenon, nicknamed the “Painted Desert”, was formed when the area was once a river floodplain. Each colour corresponds to a different underground geological feature – rocks which have seemingly dyed the layers of earth above. Formed from volcanic activity, the hills at the John Day Fossil Beds National Monument in East Central Oregon, USA, are almost bursting with colour. Pictured: The colourful hills at the John Day Fossil Beds National Monument in East Central Oregon, USA. (Photo by Mark Brodkin/Solent News/SIPA Press)

The number of soldiers on both sides of WWII that were killed or went missing is just staggering. Now, the mystery surrounding one RAF pilot and what happened to him and his plane has been solved after 70 years. RAF flight Sergeant Dennis Copping climbed into his Kittyhawk P-40 aircraft in June 1942 to fly the plane to another airbase for repairs. He was never seen or heard from again.

Passengers from the ferry sinking off South Korea's southern coast are rescued by the South Korean Coast guard in the water off the southern coast near Jindo, south of Seoul, on April 16, 2014. Almost 300 people were missing after a ferry sank off South Korea on Wednesday, the coastguard said, in what could be the country's biggest peacetime disaster in nearly 20 years. (Photo by AP Photo)

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.