A stewardess holding a lightsabre poses for photos with visitors during a tour of the Star Wars themed All Nippon Airways ANA R2D2 Boeing 787 Dreamliner aircraft at Singapore's Changi Airport November 12, 2015. The aircraft was opened to the media on Thursday as it makes its first Asian stop outside Japan. (Photo by Edgar Su/Reuters)

Members of the Albert Battery perform a gun salute during the Anzac Day dawn service held by the Currumbin RSL on the Gold Coast in Currumbin, Australia, 25 April 2016. The Anzac day marks the landing of the Australian and New Zealand Army Corps (Anzac) troops at Gallipoli in what is today Turkey during WWI. World War One, also called the Great War, according to official statistics cost more than 37 million military and civilian casualties between 1914 and 1918. (Photo by Glenn Hunt/EPA)

A man presents a self-made robot that local media reported is able to carry a person, in Heihe, Heilongjiang province, China, April 5, 2017. (Photo by Reuters/China Daily)

A wounded Syrian girl looks on at a make shift hospital in the rebel-held area of Douma, east of the capital Damascus, following shelling and air raids by Syrian government forces on August 22, 2015. At least 20 civilians and wounded or trapped 200 in Douma, a monitoring group said, just six days after regime air strikes killed more than 100 people and sparked international condemnation of one of the bloodiest government attacks in Syria's war. (Photo by Abd Doumany/AFP Photo)

“The RSPB’s Snettisham Nature Reserve lies on the edge of The Wash, one of the most important bird estuaries in the United Kingdom. The Wash, on England’s east coast, supports over 300,000 birds, and Snettisham sometimes holds more than a third of them”. – The Palm Beach Post. Photo: Waders flock together seeking new feeding grounds during the incoming tide. (Photo by Dan Kitwood/Getty Images via The Palm Beach Post)

Growing cities, overuse of fertilizers and factory wastewater have degraded China's water supplies to the extent that half the nation's rivers and lakes are severely polluted. China aims to spend $850 billion to improve filthy water supplies over the next decade, but even such huge outlays may do little to reverse damage caused by decades of pollution and overuse in Beijing's push for rapid economic growth. Photo: Fishermen row a boat in the algae-filled Chaohu Lake in Hefei, Anhui province, June 19, 2009. (Photo by Jianan Yu/Reuters)

“Maya” girl Ines de la Paloma, 9, (L), sits with her friend Nuria Sanchez Caballero, 6, at an altar during “Las Mayas” festivity in Madrid, Spain, May 8, 2016. “Las Mayas” festival is held annually at the beginning of May to celebrate the awakening of nature in Spring. Young girls are chosen to become “Mayas” and sit at altars decorated with flowers so that people can admire them. (Photo by Susana Vera/Reuters)

A man feeds a seagull during a record low tide in Saint Malo, western France, March 21, 2015. Towns on France's North Atlantic coast braced for their first giant tide of the millennium on Saturday as the full moon and this week's solar eclipse combined to create an ocean surge not seen since 1997. (Photo by Stephane Mahe/Reuters)