A donkey carrying sacks of coal walks through the narrow tunnels of a coal mine, in Choa Saidan Shah in Punjab province April 29, 2014. Coal miners in Chao Saidan Shah use donkeys to transport coal from the depths of the mines to the surface. (Photo by Sara Farid/Reuters)

Britain's Red Arrows airplane display team perform during D-Day commemorations in Portsmouth in southern England on June 5, 2014. Several hundred surviving veterans of the 1944 D-Day landings are commemorating the 70th anniversary of the mission on both sides of the English channel. (Photo by Carl Court/AFP Photo)

The Royal Air Force aerobatic team, the Red Arrows, perform during The Royal International Air Tattoo at the RAF in Fairford July 11, 2014. (Photo by Stefan Wermuth/Reuters)

An enormous crocodile mauls a young hippo calf carcass near Lower Sabie on May 11, 2014, in Kruger National Park, South Africa. An enormous crocodile tosses around a young hippo calf caught in its lethal jaws. The giant reared out of the water revealing a young hippo calf between its teeth. The huge beast then span, jumped and splashed in the water with the small carcass. Amateur photographer Roland Ross captured these incredible photographs near Lower Sabie in Kruger Park, South Africa. (Photo by Roland Ross/Barcroft Media)

The 2012 Magic Art Special Exhibition Of China is now open at the Hangzhou Peace International Exhibition and Conference Centre of the Chinese city of Hangzhou.

Photo: Visitors poses with a 3D painting during a show featuring over 50 such works in China on July 20, 2012. (Photo by Associated Press)

The public get the first view at the opening of the new miniature model Knuffingen Aiport at Miniatur Wunderland on the airport's opening day on May 4, 2011 in Hamburg, Germany. Miniatur Wunderland is the world's largest model railroad landscape, and the model airport, also the world’s largest, goes into operation following 6 years of development and construction and an investment of EUR 3.5 million. The airport is a reproduction of Hamburg’s international airport and includes 40 aircraft that take off and land and 90 vehicles that autonomously move around the runways on May 4, 2011 in Hamburg, Germany. (Photo by Stuart Franklin/Getty Images)

An Aerial view Admiralty Arch at the top of The Mall on July 26, 2011 in London, England. (Photo by Tom Shaw/Getty Images)

Buddy Bears are a series of painted, life-size fibreglass bear sculptures originally developed in Berlin, Germany. The first Buddy Bear was created by the German businesspeople Klaus and Eva Herlitz, in cooperation with the sculptor Roman Strobl in 2001.